These are some of the interesting cases we have had at MTech, which I've reported at Bulletech.
( If I have overlooked yours, and you would like to see it here, Pl feel free to mail me a reminder ! )







The Search for Stability Metallurgy of a Hot-Rattle The Jinxed Bike meets MTech
Another cause of Retard Stop the clatter before it stops you ( Pt I ) To Kill a Thunderbird
Wheel Bearings Mystery Stop the clatter before it stops you ( Pt II ) Erratic gear-shifts are funny ?
Taming of the Spark How to un-bend a chassis ! :-) Done For, not Done-Up
Bushes won't leak if Plugs don't ! Debugging the LB500 Insulation intrigue !
How to snap a Clutch-cable Our B2B job ...was a challenge !      
     
     
     
     



The Search for Stability

Hi,

This fairly new Bullet in for a service was a bit unstable.
Alignment was fine. Tyres were well inflated & uniform. Bearing-check reveals play in swing-arm !!!!
WHAAAT ?!!!
The owner chimes in that his friend had also told him that " rubber-bushes " needed to be changed.

Not so fast ! Not at MTECH !!

Firstly, the rubber-bonded-bushes have a LONG life. Secondly, when they shred, they feel squashy.
Here, play was nil-resistance ending with a clack ! Loose swingarm-axle-nuts ! I said.
An apprentice put ring-spanners on them and leaned.
Nada !
Heck, now what ! I scratched my head.
Low miles, good adjustments, good tyres, good bearings, ...weaving bike, free, clacky-play !
Any which way, they added up to loose s/a axle .......which BTW was " tight " !
........ or was it ?!!!!

I took a closer look at the axle nuts & stud.
Ah-haa !
Mon-day in Chen-nai ! Nine-teen Eighty-Four ! ( Sorry, Sting ! )
My mind rewound to when I'd a broken main-tube in my new Bullet due to the same careless assembly.

With a ring-spanner on one side and a socket and a tommy-bar on the other, I could turn the axle-nut
about 3 turns before the plates really bottomed out.

The torque-setting on the air-wrench at works had let go, mistaking tight threads for end-of-threads.
Tsk !

First use your eyes, then head ! says Colin Campbell.
My New Year Resolution .......EVERY year ! ;-)

The customer had impatiently gone for a test-ride, and he returned standing on the footpegs with folded hands.
" ...straight as an arrow, stable like a rifle BULLET !.... " he said.
Cheers ! I said, You're lucky it wasn't bushes !
Some Authorised Dealer just lost Rs 400, I thought.

Regards,
Nandan.

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The other cause of Retard

Hi,

We also had this another interesting case.

The exhaust bend was more yellow than usual.
Starting trouble ? I asked at sight, sure that the ignition timing was well retarded.
No, but the mileage is lousy said the owner, and also the top speed is disappointing.
Hmmmm. I was on the backfoot.
It's just been serviced by ******s but there was no improvement, the owner volunteered...
I suppressed a grin. ******s was a 5-star-garage as renowned among the newbies as notorious
among the veterans and someone talking of it with reverence was asking to be gypped again.

Luckily he was at MTech, where the emphasis is on Bullet-eer-ing & not on profit-eer-ing.

My grin was just about turning into a grimace as retarded engines do not start easily, but
then the tube lit !!!
Ohhh ! The centrifugal-advance is jammed, I said without even bothering to strobe it.

A road-test managed 80kmph at best.
The apprentice had the points-cover off in seconds and twisted the cam, which was free.
He looked at me half-resigned, half-leering. But I'd already thought this thru.
I said The tail may wag the dog, but can the dog wag the tail ? TAKE OFF THE POINTS PLATE !!!
Yah !
Pulling on the centrifugal-weights did not turn the cam ! The mechanism was effectively jammed !

What exactly was wrong ? It was a new bike, no grime, rust or hardened grease.
Nothing so very obvious !
But a patient examination in good light paid off.
The slot in one of the weights was extra-shiny and it's corresponding pin had a gouge.
Further examination revealed a slight tilt in the pin.
A manufacturing defect during rivetting, because the part is far too sturdy to get damaged so later.

We substituted the cam with one of ours and tested the bike. 110kmph ! Bulls-eye !

The apprentice was still not fully convinced; he didnt actually accuse me of practising witchcraft,
but that must be because I pay him well.
Well, it turns out he could not grasp/ swallow the diode-action of the jam.

You can't climb a fence leaning towards you !
Too cryptic for him so I'd to show him how turning the cam bore the pin on the outer of the slot
at a obtuse angle, while pulling the weights bore the inner side of the slot onto the pin which
made an acute-angle.
The penny dropped. He smiled sheepishly. But I do dare say he's going to be better than any at ******s.

Regards,
Nandan

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The Wheel Bearings Mystery

Hi, guys,

I must have bored some of you to tears with my " fishing " stories about Bullets,
but how about ones that got away !!!
:-)

We had this Bullet with a bad wobble in the rear wheel and it was no surprize to
find both the hub bearings shot.
We all know that India-bearings are s*it, and they have a pretty short life anyway ( yah,
replace them with Genuine Brit Branded bearings or Modern Branded Bearings and you are
assured of Rock-Steady-Idle & Crisp-Seamless Acceleration & Increased Top-Speed, harr )
so I just let the apprentice replace them with sealed SKFs.

You guessed it !

The bike was back in a week, with a similar wobble again.
THAT got my attention alright !
( Yeow ! Ranging rifles outatheway ! Load the heavy artillery ! )

The ( shot ) bearings LOOKED properly installed, squarely oriented and firmly gripped.
Hmmm.
On a hunch ( after more time than I'll admit to :- ) I prodded the " bobbin " between the bearings.
AXIAL FLOAT ! Ah-HAA ! The hub had been sleeved to improve bearing-fit.
But by the wrong mechanics !
( But Forgive them, Father, for THEY are the ones who teach us the really interesting stuff, not PP marketeers )

The diameters were OK, but not the distance between bearings !
The axial load of the axle-nut being tightened was being taken, not by the bobbin but by the races !

YET another addition to the list of dud-bearing stories which turn out to be actually poor-installation.

ALL bearings are " Electroslag-Refined "
ALL bearings are " precision-ground " and
ALL bearings " laser-inspected "
What abuse Chinese/ Taiwanese bearings can't take, you betcha life Swedish/ Swiss fellas can't either.

Show me a fella who says otherwise, and I'll show you a con-artist marketeer or an utterly incompetent fraud
who does not know bearing-installation basics.

To come back to the story ( remember ? ) I felt obliged to replace the bearings spoilt due to my carelessness
though the customer ( a friend ) was not in the least inclined to demand free replacement.
He was even game for further experiment.
Between a couple of cheapest 6203s we put the bobbin and a cyanoacrylated stack of washers ( ID 17mm )
such that the inner races hit the bobbin simultaneously with the outer races hitting the step in hub ( or earlier )

The cheapos are running fine to this day, thankyouall.

Someday we are going to re-sleeve the hub properly or make a custom-bobbin .....
...... or atleast tackweld the washers together ! ;-)

Regards,
Nandan

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Taming of the Spark

Hi,

We recently had a CDI bike running erratically.
Very soon we discovered it was due to the HT sometimes jumping
to chassis from near the beginning of the HT cable.

Hmmmm.

It turned out the coil had been changed quite recently too !

Twice is NOT coincidence, not at MTech, sorry Goldfinger ! ;-)

While the Jury was debating the probablity of cable chafing on the
chassis, exciter voltage being too high, CDI unit being substandard,
the coil being substandard, I, Judge, had pronounced the Verdict :
The Plug or the Plugcap.

( Couldn't resist the swagger, :-) )
but fact is, the reasoning is quite elementary.
It takes no Sherlock H to nail the culprit above.
It must've struck you too already, otherwise pl give it a bit of thought )

Bypassing the plugcap made the engine run better than it had for weeks !
So plugcap, isn't it !
......WHAT ?????????
A passive part like a PLUGCAP ?!!
How ?!!

I put an Ohm-meter across it, Infinity. Kilo-Ohms, Nothing. Meg-Ohms, Pick-up.
So plugcap it is, but why !

A small rock... ooops, I meant to say " a common impact application device "
skillfully wielded by one of the Jury unveiled the cause.
The plugcap was a Resistor type, with 2 internal joints where the plain-jane
fellas have none.
It was probably a cheapo, and the bakelite molding didnt adequately seal the
inners of either terminal. All interfaces inside were green with oxidation !
The resulting resistance was so high that the HT found it occasionally easier
to jump thru the 2-layer insulation !!!

Plugcap replaced, plug cleaned etc, the engine was running sweetly.
So the plugcap was it ! ? So the coil is OK then !
Sorry, but NO !
Pierced insulation is damaged insulation.
I would atleast carry a spare if not replace the coil right away.
.....And no, we had no coils in our inventory ! :-)
The new coil won't get screwed soon too ?
Nope.
Sure ?
Hey, make your cheque payable in 2010 !

Regards,
Nandan.

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Bushes won't leak if Plugs don't !

Hi,

A few days ago a guy with a Bullet halted at the garage and asked if we could do
something about the oil leaking from his " Delco " ( contact-breaker unit )
A mess, but not alarming. A very strange case though.
Scratching my head, I missed a part of the story the rider had launched into, but
the gist was that this leak had developed recently and his mechanic had not been
able to stop it inspite of changing the " Delco " bushes, which remained leakfree
only for a couple of days.
Every mechanic he met suggesed the same remedy, so if I had nothing else up my
sleeve, he was off .
Otherwise when could he bring the bike for repair ?
He was not very polite, but in his shoes who would be ?!!

Ha, he didn't know it yet, but MTech is DIFFERENT.

I said I'm going to repair it NOW, and for NO CHARGE.
You can pay after you are satisfied with the job.
His jaw fell.
Where's the catch ? he was wondering.

Are you too ? :-)
Hahahaha, you should be more attentive at Bulletech !

The crank-plug !!!!!!!!!!!!!!
If that cork cracks, oil is pumped not into the crank but into the timing-case and
then back to tank.
If the overflow hole to tank is too small to take the entire flow the level of oil in the
timing-case rises & it seeps out from the Contact-breaker assembly.
If the overflow hole is big enough though, you'll have no " Delco " leak.

Sure enough, the cork was in 3 pieces.
( The apprentice was ZAPPED ! Black magic ? X-Ray ? )
Replaced it with a neoprene plug in a minute and waved the fella goodbye.
The admiration on the Apprentice's face had turned to disgust.
Why didn't you charge him ?!!! he said.

He was a bit sheepish when the rider was back 4 days later to leave his bike for a
total overhaul, ( NOT free ! ) so impressed was he with our " repair " !

Damn, I should have this group archives put on a CD !

Regards,
Nandan.

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Metallurgy of a Hot-Rattle !

Hi.

rat-a-tat-a-tat-tink-tink-tat-a-tat- I winced as the bike parked outside our garage.

Intros over, the rider launched into his story which was actually rather superficial. He
had been to mechanics near his house, and then some " famous " ones, then checked
the internet, read of Hot-tappet-adjustment and repeated the cycle.......in vain !
The engine still rattled badly whenever it warmed up.
He looked at me accusingly ( it may be my conscience on overdrive ) as if I had
remote-hex-ed his bike or something.

He hadn't actually said You need not say anything, but anything you say will be recorded
and may be used as evidence against you, but he seemed that sort of a guy.
So I chose my words carefully.

You should be gentle with plug-hole threads I said.
Especially when they are hot. If they stick, unscrew and start again. Maybe with a dab of
oil. And if you are still unfortunate enough to strip them, be doubly careful with the
repair. Don't go to any ol' frying pan repairer, go to a mechanic who knows metallurgy.

His look had changed from shock to interest and he could hardly wait for me to wind up
my lecture. Yes, yes, yes, he said. This problem did start after the same repair was done
by ******* ( illiterate veterans ) but how can you guess, where is the CONNECTION ?!

Over a tea & cigarette ( he paid for both ) I told him.

But I am not going to tell you ! :-)
Not because you won't buy me a tea & cigarette ( many of you have sent me gifts worth
hundreds or thousands of both ) but because you have guessed what the " connection " is.

To prevent me from launching into Pt-2 of this " fishing story " someone finish it off soon !
:-)

Regards,
Nandan.

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Stop the Clatter before it stops you ( Part I )

Hi.

Some days ago, a friend & client called me to complain that his bike would
stop every ten minutes or so, and start only after a several minutes rest.

I was onto auto mode before he finished, and absently rattled off possible
causes : tap, float-valve, cap...

To be interrupted by a pained : It's ME, xxxxx here.

Ooops. Yes, he wasn't a newbie, he would have checked all the obvious ones
already. OK, so YOU tell me, Holmes ! I said, suppressing a grin.

Hmmmfh. He snorted. I bet you think it's funny ! You'd not be laughing if
you were stranded with a sometimes running sometimes clattery eng...

He'd last called when about to check rocker wear !!!!!

CLATTERY ?!! Why didn't you say so in the FIRST place !
I managed in the midst of a merciless laughing fit.
You mus' be off your rocker ! You SLAY me...

Literally, literally, Jerome David Salinger ! he threatened as he hung up.

The sudden change of tone from disdraught to mock-threatening banter
was a clue that he'd caught the clue.

Did you ?

Regards,
Nandan.

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Stop the Clatter before it stops you ( Part II )

Hi.

Hi, Nandan. ( It was xxxxx on the line today )

Hi. ( Did it take him ALL these days to.. )

How are you, Nandan ? I have a problem.

Don't we all.

I mean my bike, he said. It won't pull.

Tell me about it. What did you do so far ?

Nothing. I'm stranded, he said gloomily. It ran like a champ after I fixed it ....
after speaking to you... but it's got a bit moody lately. Wouldn't pull well. It's
been deteriorating a while, now it only starts but doesn't pull at all.

Crazed plug, closed points... but I didn't want to risk his pained whine again,
so I said nothing.

Well ? Any ideas ? he asked impatiently.

Hmmm, I thought. He fixed it. Deteriorated swiftly ! Doesn't pull ! Aah, plugs
& points don't deteriorate SO fast.

Hello ? Are you...

It's CLATTERY, right ? Real BADLY, right ? YOU really NEED a torque wrench, right ?
( If you think that one was under the belt, then what about this one : )
If you can't fix it RIGHT first time, may I recommend a GOOD Bullet garage....

Yeah, I'm coming to MTech. Not for repairing my Bullet. For repairing YOU !

I did not reply; I couldn't. I was laughing too hard. He had joined me in the
laughter as he hung up. So he'd caught the clue.

Did you ?

Regards,
Nandan.

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How to un-bend a chassis !!! :-)

Hi.

A newbie called to enquire why his bike was pulling to one side. I told him
some usual possibilities, but I soon realised it wasn't going to work; it was
all jargonese to him.

He had been trying to get an old bike, newly purchased by him, sorted at his
nearest mechanic... unfortunately, a pakistani running high on charisma
....& low on tech !

Finally he decided to take the long ride to MTech, but not with much hope
because he had been told in no uncertain terms that his bike had a bent
chassis and he should never have bought it.

Swing-arm & fork check, wheel trueing, new bearings, new tyres, ...the list
was long. And the story was sad... SO FAR !
A happy ending was in plain sight ( if you knew where to look !! )

It was a 70s Bullet, with rear-hub converted to QD type. The front-hub had
been modified to take the speedo-drive. I took a closer look at it.

You need a front wheel rebuild, I said.

But... he said ( it's just been done ! ) ???
I really did not want to know his thoughts then ! :-)

I checked that the rear-wheel was centered in the swing-arm and drew him
a map to find my favourite wheel-trueing fella.

If that doesn't cure your bike, come and collect whatever you pay him, I said.

That woke him up ! :-)

And if you go to any other guy, tell him to centre the rim to axle, NOT hub !

No, he didn't catch the clue.

But you did, didn't you ?

Regards,
Nandan.

PS : Of course, it worked ! ...Wouldn't be telling it here if it didn't ;-)

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How to snap a clutch cable

Hi.

This's been triggered by an email from an unknown Bullet-eer, but it's common enough :

Frequently snapping cables in 5-speed GBs.

Everybody knows from 4-s experience that the cables always snap at the lever end.

But the 5-s cables snap at the GB end ! :-)

The clutch-pusher has been re-designed since the early days, but breakages continue.

It's because most mechanics didn't know the difference between a cable-adjuster &
a clutch-adjuster.
The formers are on the clutch-lever & on the back of the GB.
The latter is under the " 5-Speed " label.

You got the clue,

Didn't you ?

Regards,
Nandan.

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The Jinxed Bike meets MTech

Hi,

We had this old but well looked after bike in for a service, it's first at MTech.

It needs new plugs & battery-charging too often, but otherwise is perfect, said the owner.

Meanwhile I was attempting to start the bike, and noticed that the ammeter barely deflected
with the points closed. The engine was hot from the long ride; maybe the battery was dead ?
Horn was piercing, headlight blinding.
Ohh !

Points must be pitted, I thought, or the wiring is frayed; maybe the ignition switch is dying.
( It was a 6v model with a multi-pole ignition-switch )

After visual inspection and by-pass jumpering, the apprentice reported it was :
d) None of the above.

( Eeee ! WMD !! Bring on the Heavy Artillery !!! )

Hot-wiring the coil thru a digital ammeter showed a primary current a shade below an ampere !
( Hardly a quarter of the normal current )

Switching to Ohms Range confirmed the coil had a odd, high-resistance primary.... 7 Ohms !
( Maybe meant for a batteryless engine ? )

Switching the coil with a normal 6V one made the spark look like lightning instead of the
glow-worm it previously was.

Now starting needed a gentle prod instead of the previously mandatory vicious kicks.
It fired first kick on every single " old, defective " plug in the toolbox !!!!
Ran without misfire at any speed.

The owner was thrilled. It's never run like this since I bought it, he said.
Every mechanic used to change the points, plugs & charge the battery.

Every mechanic, I smiled, is not an M.E., and does not read Frank Price or Robert Pirsig.
Every garage is not MTech !

Regards,
Nandan.

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To Kill a Thunderbird

Hi,

Here is another way to kill your TB, ( as if you hadn't enough already )
but
forewarned is forearmed,
and
a word to the wise,
etc.

We saw this absolutely frazzled AVL recently, it did not take any intution or experience
to say that it had been run for a while without adequate ( read : any ) oil circulation.

The owner was shocked, as it had been running " like a champ " till it inexplicably lost
all steam a day " or so " ago.

He was sure the oil was good & the level was right, as he'd recently washed & serviced
the bike himself.

Did you change the filter ? I asked.
I cleaned it with compressed air, he said, ( not meeting my gaze, but I let that pass )
I meant the Oil filter, I said.
uunnnhh...no, he said guiltily.
Good. I said. ( I've heard of cheapo filters getting pulped and clogging the lines )

There was no oil-flow at the filter, nor at the tappet-window. We pulled the timing-cover.
Ugghhh.
The pump-shaft was chewed & so was the worm.
I've seen many of those, but usually the guys get to a garage before it does much damage.

This fella had driven till the bike stopped, and then pushed it to a shade-tree-mech who
" made it ready " by putting some oil in the bore & the petrol. But it had " lost pull "

There were no blockages apparent to oil-can.
The engine was coming apart anyway to change bore & piston ( hopefully not big-end too ! )
so I turned again to the timing-case.

The pumpshaft was jammed. Maybe the damaged part of shaft had splayed..... but no.
Odd... Not the gear-pumps, surely !

As I removed the endcaps, I realised they had been screwed in very, very, very tight.
I used a wad of cloth to prevent the Allen key from cutting into my hand, and the owner
smiled slowly but smirkingly :
*I* have a ratchet-dri... He stopped abruptly.
Because the pumpshaft was now turning freely !

I tightened bolts in all the leaky places, he said in justification, as I removed the endcaps.
And a lot they must have leaked ! In the grooves were O-rings of visibly smaller section,
that had no chance of sealing the joint at all.
He could not ( or would not ) recall who had installed those, but it was not REM for sure.

Regards,
Nandan.

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Erratic gear-shifts are funny ?

Hi, fellas,

So there was this guy who had come to collect his serviced Bullet.
One of his complaints had been that the gearbox could not shift as fast as he wanted it to.
Deja vu, ad nauseam, such riders, who hasn't !
( Yah, design, envelope, performance, macho, yah ) ..........but never such a gearbox !!

But Devils do not come to Church, so I decided there must be a misunderstanding.
On a re-run it became clear that his gb was fine on slow changes, but on rapid shifts
during acceleration it would go limp....

The shifter had been thru a fine-tooth-comb and I'd found everything perfectly normal.
In fact, it was far from needing service, let alone repair.

And this fella was not the snooty/ macho liar types. His problem was genuine.
But what ?

Can you recollect when this problem started, I asked.
As he was scratching his head for the answer, I was doing much the same about the problem.
A possible reason slowly dawned upon me.

" Take a trial now, but use my slippers " I said.
" But..... " Words failed him.
" Humour me " I said.

I'd picked that old sawfrom "Jaw" and had been itching for an opportunity to use it. :-)

WELL worth the wait, it left him gaping, gasping !!! ;-)
He exchanged footwear in a trance and was off on the trial run. He returned in the same state.
" It's OK now " he said , the quaver in his voice was distinct ! :-)

Terrifying; witchcraft-ridden ( p. not i. ) bike !!! :-)

Poor fella. If only he had been in his normal senses, the answer was SO simple !!! :-)
His shoes had truck-tyre-like soles, and he was now wearing my slippers, worn thin.
Because of his heavy and thick-soled shoes, he had been not letting the gb lever back up
enough to re-engage the ratchet during rapid-repeat-shifting !

This problem started when you bought these shoes, I said prophetically, wondering
whether to add that Bullets don't take kindly to snotty Branded footwear
( tho' actually made in Sudan by slave labour ) but
by now he was onto it too.

I would have ditched the shoes but he was far too enamoured of them
( having paid a fortune for them )
So we lowered the gear-lever a couple of splines and that worked almost as well.

Regards,
Nandan.

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Done For, not Done-Up !

Hi,

Chopper bars, two-tone paint, lotsa chrome, gleaming alu.
Sponge-shoes, branded-jeans, S&S tee-shirt, pimple-face.
College " student ". No doubt.
Pushing the " Bull ". No surprise.
Doesn't run, he said.
No Sherlock, I, but I'd deduced as much already. Pass.
Needs toppit ajjustment, he added.
Let's begin at the beginning, I said.

His bike'd been " Done up " by a " 2-wheeler speshallist " and just when it was cool, like, it
suddenly developed these heating & noise & smoke issues, like.
HIS " mecha " finally told him to take it to any Bullit specialist and get the toppits adjusted.
OUR Chief Mechanic trod on the K/s and reacted as if he had stepped on an anti-personnel
mine. We all knew it wasn't toppits ( ooops ! ) but this was looking BAD.

We looked accusingly at the doood, and some more facts tumbled out :
After reassembly, it ran for a few kms but with noises and then it began to smoke.
Like hell, like.
They had changed plugs, petrol and then the oil, but it became only worse
and finally packed up completely.

That was better ! No toppits this time.
( When dooods talk of toppits, I worry...
Terrible thing, toppit ajjushment ! The single largest cause of downfall of many a smart toooner,
it is also the first thing every apprentice & doood rushes into. So when dooods talk of toppits,
I worry. I also worry when dooods talk of clutch-slip, or beats or gas-flowing or NOX-Bulls,
or chooths talk of sicoolarizum, but that some other time, place... )

Finally, after the doood accepted that it had to be repaired, toppits or whatever, we got round to it.

There was oil in the tank, but the engine felt like it had seized from want of it. The plug was fouled.....
suddenly the jigsaw pieces made a picture !
A terrible one, actually : top-end lube-failure !

Sure, there was PLENTY of oil in the sump, but rockers had been badly mauled, pushrods were buckled
and there was blueing and flakes all over.
So it all pointed to the scavenge pump.
No, it wasn't even High Output ! ;-)
It was hardly worn, and good for another decade IFF it had been lapped/ greased/ or primed on assembly !
OR the dooods had looked for oil-flow on start-up !
( After, corblimey, buffing the timing-cover ! )
For the lack of a few drops of oil, a bit of knowledge and some discipline, it sure was a very grim harvest !
A WHOLE lot of parts to replace !

Not to forget, finally, tappet adjustment too ! ;-)

Regards,
Nandan.

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Insulation intrigue

Hi,

Mechanics hear the corniest of stories.
Stories that should have been told to doctors :
This bike gives me a back-ache/ elbow-pain/ shoulder-ache...
Stories that make bill-collectors smile :
Oh-oh, I forgot to bring money but I need the bike now...
Stories that could be told by Baron Munchhausen :
...used to do 140kmph upslope, giving 50kmpl, but now...
Stories that set alarm bells ringing :
Ma Bool wuz smooooth as buttuh in d showroom,
but d dealrz ppl screwed it in First Service, tottly like.

Mechanics soon develop a filter between their ears & brain
that block & prevent such spam stories
from wasting their time & mental resources,
while actually amplifying the reporting of true technical observations.

Sort of Dolby Noise Reduction ;-)

The transition, however, is not sharp as in a Chebyshev,
maybe more like a Butterworth filter...
and some stories suffer an undeserved fate.

This is a story about such a story.

So one day a voice on the phone told me that petrol & beer were free from now
& India had declared war on paapistan.
Ooops. That can't be right ?
Not with senile-puppet Maunmoansing as our PM !
It was my Filter-Interpreter running amok.
I switch it off and say : Enh ??
This time the voice said :
...in one kick, hot or cold, but after riding for an hour, if I park for an hour, it won't start at all...
Oh, so my filter WAS functioning fine !
This must be a case of clogged Air-Filter
running the bike rich, so it wasn't easy to start hot.
I did not want prolonged discussions about hot starting methods,
nor arguments about his obviously biased observations,
not with a strange voice on the phone, so I just told him to go get the bike serviced.

Maunmoansing has resigned and intends to migrate to Italy
to work as Pvt Toilet Cleaner for Quattrochhi.
Nandan, they want to know if you are willing to be PM...
OHHH-NNNO ! So it was the Filter-Interpreter again.
I switch it off & listen:
...got it serviced like you advised, but there is no change.
I told the mech the whole story, and he says it needs a rebore...
Uh-oh ! Innocents are in jeopardy here !

I have no idea why a engine will start hot or cold BUT not warm,
but I know the remedy is definitely NOT a rebore.
Even as he talked, I got some faint clues...it was obvious actually,
it's just that I had not listened to the guy with an open mind until now.
What a bad attitude ! :-(
My Filter really needs a recaliberation !
But, hey, OTOH, I never sell unnecessary rebores...

So I told him to bring over the bike, preferably hot,
and see if my suspicion was correct.
#1 Ionisation voltage of spark-gap falls with increasing temperature
#2 Breakdown voltage of dying insulation falls with incr temperature
#3 Newton's Law of Cooling.

Superimposing the three, it is quite conceivable that at some intermediate time,
the exposed engine is cool but the coil
crammed in the frame above the engine is still hot ( enough ) and...

So the guy brought his bike, good & hot, and I restarted it a few times.
It started crisply each time & revved freely on load.
Hmmm. An hour later, I gave it a normal kick.
Dead as a dodo !
Rich ? I opened throttle & leaned it out and then tried again. Nada.
Lean ? I pulled the " choke " & tried again. Nyet !
I held the HT wire close to chassis & kicked.
Feeblest apology of a spark.
It wouldn't ignite a Nano !
Much less start a Bullet engine !

I took off the tank. Removed the ign coil and tossed it on the bench.
I wired in a new one and the engine started on first kick !
I wired in the old coil again, now much cooler in the open and checked the spark.
A little better, but red, and no, it did not start the engine.
I put it in a plastic cover and tossed it in the freezer for 15 minutes.
This time, the spark was normal, blue with a click !
Engine started too.
Tesla, Lichtenberg, Newton, et al ! Thanks, guys, you sure rule !

Regards,
Nandan.

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Debugging the LB500

Hi,

It's not really a Bullet, I said as we got off the LB-500,
but as we saw, it puts Pulsars in their place rather more
easily. I began to take off the Cramster riding-jacket.

Hey ! The de-comp doesn't work ! she said, partly in disgust
partly in surprise, astride the LB, trying to kick-start it.

They don't in AVLs, I said & this one has an Electric Starter.

Electric-start a MOTORCYCLE ? She stared at me in disbelief.
Someone told me electric-starters were for scooter-riders with bangles ?!!

Guilty, I said. But this one's a 500. Too much compression for you.
Anyway, let me show you the kick-starting drill.
But my daughter had already started it with a vicious kick from ~TDC.
I winced. It was a good demo of her kick-boxing skills,
but not quite something anyone could pull off consistently
in heavy traffic situations.
She'd realised that too, for she then patiently witnessed my demo & discourse :

Press the kicker till it stops moving freely.
Then bring it to 8 o'clock, using the clutch.
Put your weight on it so it goes to 6 o'clock. ( takes a bit of practice to not lose balance )
Now it is exactly like a decompressed, initialized STD...
a gentle, long kick will start it easily & consistently.

She tried it out a couple of times & nodded : Better. But why
couldn't they just make a de-comp that works ?

Search me, I said, maybe they knew most of the AVL customers
would use only the electric starter ? Maybe they expect only
overweight dumbos to buy AVLs, not svelte & smart girls ?

They'd be correct THERE ! she sneered, no Neutral-finder.
And no de-comp either ! An extra, un-necessary gear instead !
Wrong side shifter !
I prefer my STD Bullet any-day ...but then, this LB-500 REALLY zips
& it doesn't look half as ludicrous as the thunderbirds... it's a nice back-up bike.
Fix it, Pappa, and buy it for me.

Ouch, a Left & a Right !
I didn't know which was more difficult, to correct design-blunders
or to scrape up a huge fortune that used Enfields now cost !

I did know I was going to do BOTH, only not HOW... Yet. ( sigh )
( I'd never bought her bangles; I wasn't starting now )

I recalled the inside of the cylinder-head, looking for place to fit a decompressor.
Then dismissed the idea as unwarranted complexity...
( If you can't keep it simple, go the whole hog : just go JAP ! )

We all know the stock AVLs cannot be decompressed.
The whole de-comp system feels on the verge of break-down without
even a hint of the exhaust valve being about to budge.
But what exactly would fail if we persist ?
What if we strengthen that ?
Would something else fail or would the valve open then ?
We could consult AVL/ Egli, or we could just try it & see... ;-)

A determined push of the de-comp resulted in the cable popping out
of the broken end of the plastic lever. Not quite Kevlar, eh ?
What would go next ? Collar, cam, lid, splines, lever, cable... ?
I pop a ring-spanner on the lever on tappet-window & lift.
HEY !!!
The valve lifts cleanly, with very little strain !
After the darkest hour comes the dawn ;-)
No, really !!! That was too simple !
We knew Enfield/ AVL are masters at snatching defeat
from the jaws of victory, but this takes the cake !!!
After having gone thru the effort to design & fit a working de-comp system,
they are too damn lazy to do better than use the Choke Lever
of a Jap-bike-switch which has not a snow-flake's chance in hades !

The De-comp Lever Assy off a 70's STD, with a long chromed c-i/ brass lever,
is perfect for the job. Except for a harder pull, it functions exactly like the STD !

The daughter is THRILLED, with both, the working DC & obliging Pappa !
She doesn't know how easy the job was ! ;-)

Regards,
Nandan.

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Our B2B job ....was a Challenge !

Hi,

I watched with my mouth open one of my colleagues ride in one morning on a jazzed up Yamaha cruiser.
He was too embarrassed to talk coherently, but the gist was that some mechanic friends of his were
discussing a particularly bad case of disc-brake problem, the solution to which had eluded them all.
He had boasted ( must have been in a bar ) that his garage, MTech, has NEVER had an unsolved case.
So... they gave him the bike to repair !

Heh ! We are used to dozens of new customers come with bikes " repaired " by illiterate mechanics &
ask us to rectify their blunders.
But this took the cake ! B2B or what !!! :-)

Our Chief Mechanic was listening to his colleague repeat the story of repeated bleeding, downstream &
upstream; substituting the calipher, the master-cylinder, the hosepipe...
He pressed the lever, which had no resistance whatsoever, and looked at me. I nodded to him to
start working on it, but he was not to be rushed.
Woh bhi mickanicaan, saab, chattri nahin, he said. ( They too are mechanics, sir, not umbrellas )
The reference to umbrellas escapes me still, but he did have a point there.
Almost !
Like our customers, I believe that there are mechanics and then there are mechanics.
All mechanics think deeper than their customers, but WE think deeper than the roots of the problem.

I began to look over the bike ( gawd, is it ugly )
A bunch of superficial bling-mods or doood-mods :
paint, chrome, h/r handlebar, twin-h/l, fat-wheel, topped off with a "diks conversion " ...Yech.

At the end of those brilliant observations, ;-)
I was still cluelessly fingering the limp lever and wondering how it could be so if they really
had substituted everything AND bled it properly.
I looked again at the stupid hi-rise-bar on which had been bodged a... HEEEY ! Whoa ! Whoa ! Whoa...

Never ask me to write an essay on Roman Aqueducts, I only know water finds it's own level and that
air is lighter than any hydraulic-fluid. Which is still more than could be said for mozzie mechanics.
The fluid-reservoir was at a steep angle with the banjo at the top, probably well above the level of
the tank-to-master-cylinder-port !!!!!

I triumphantly tapped the banjo and turned to the Chief Mechanic to explain the scene. But I did not
have to say anything. He had been observing me & had accurately guessed what I was thinking.
He removed the m/c assy from the bar & opened the lid of the reservoir. Injecting some fluid upstream
removed the culprit bubble and it's done !!!

We did not charge for the repair...
Nor do the knights who retrieve the glove from the lion-pit... but, IIRC, they fling it at the face
of the careless owner !
So I told my colleague to tell his friends :
Ustaad ustaad hota hai, aur shagird shagird.
( A master is a master, and a learner a learner )

;-)

Regards,
Nandan.

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By B. R. Gurunandan

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