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2004 Speed triple
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Discussion Starter · #1 ·
Last week when starting my 955, i noticed there was a loud clunking sound when it was turning over.
To me, it sounded like the sprag and I also noticed my bikes battery was a bit low.
I pulled off the starter motor cover and found the idler gear missing 3 teeth. One of them still sitting just inside the case i grabbed out. The other 2? not sure...
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There is some damage to one of the teeth on the starter pinion too and surface marks on the others.
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So I figure i'll replace the idler gear and starter motor - but my concern is it happening again - or why it happened to start with.
Checking the sprag without taking the next cover off the motor, I can turn it one way but I cant turn it the other.
Is it worth going through the pain/price of gaskets to remove the next cover to check the sprag closer if it 'feels' like its functioning with my fingers?

I found this post : Looming failure of upgraded sprag assembly in which someone has a similar issue, though they already put in the newer sprag kit.
The explanation for damage from Joe being : 'The damages occurs when the gears are repeatedly shock loaded from a slipping/failing sprag.'
Would my sprag have been slipping if my battery was low on charge when i tried to start it?
Should I do an oil change to try find the missing 2 teeth? or will they somehow find their way to the oil filter/screens? - or do I need to pull the sump off?

Also in the below image, some part of the cover is missing - but found it missing in some pics online too (Sprag (Starter) Clutch) - is that just cosmetic?
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My biggest concern is replacing the starter and idler gear, and trying to start it but causing the same damage straight away...
 

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Went through almost identical starter/idler failure two years ago on my '05 1050 '05 speedy sprag clutch, starter, solenoid service.... If you can't find all sheared off teeth I'd change the oil but not remove the sump. For the price of cork gaskets and an extra hour or two I'd remove the sprag cover and check it off the bike for galling, scuffing other signs of wear. Congrats on excellent, clean seal surfaces and starter case interior, my 1050 looked a lot dirtier.
 

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Discussion Starter · #3 ·
Went through almost identical starter/idler failure two years ago on my '05 1050 '05 speedy sprag clutch, starter, solenoid service.... If you can't find all sheared off teeth I'd change the oil but not remove the sump. For the price of cork gaskets and an extra hour or two I'd remove the sprag cover and check it off the bike for galling, scuffing other signs of wear. Congrats on excellent, clean seal surfaces and starter case interior, my 1050 looked a lot dirtier.
I've ordered T1221112, which includes the sprag and gear which I understand are the upgraded parts.
Found a good idler gear too, just need another starter motor and the whole set of parts in the setup will be changed....
What a **** of a thing to have happen though - but that's the pain of 20 year old bikes...
 

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... idler gear missing 3 teeth. One of them still sitting just inside the case i grabbed out. The other 2? not sure...
(A)
... Hate to do the work to have these rattling around - might get lucky - drain oil/ cut filter open to check theres - if not see if could be fished out with a magnet (not greatest way - careful magnet not become stuck, wedged or loose). Otherwise inspect openings as you go along.

Get feeling yours '02 and up(?), won't have to pull motor/ split case to change sprag if that's the situation.

Below's a thread that might answer some of your questions on how to avoid trouble too...


The sprag failure itself's generally by a weakened spring from - "frozen" clutch plates creating some spinning resistance (recommend engaging clutch, rocking back & forth before starts, and only starting in neutral) - weak battery/ charging/ cold weather battery degradation (extending motor revolutions it takes to fire igniter and all, stressing spring)...

Some say they've (somewhat experimentally) replaced only sprag spring with a "fork seal spring" with varying success/ failure.

- If odometer over 50k or a lot of fast acceleration & stops (i.e. racing, street or track), also consider replacing cam chain, guides and tensioner (all affect timing, quick starting and sprag spring wear).

After you get bike tested and running smoothly, replace easy stuff too like vacuum hoses (without mixups), air and maybe fuel filter, clean/ check electrical, etc. Maybe a valve adjustment and throttle body sync after all.

If keeping, sometimes a loaner bike worth it in long run (but true condition still a gamble parts wise - some components like the one's you'll mostly want better new).

You might have a bike that runs like new after some of this.

(B)
As an aside, if unsure doing work worth it, i simply estimate:
Total "cost of labor & materials" (COL), divided by ( / );
Estimated remaining "life of vehicle" (LOV);
The sum being a partial view of your out of pocket "expense", spread out over time?

Ex:
$900 COL / 10 year LOV = $90 a year for 10 years (or $90 / 12 = $7.50 a month for 10 years).
Other factors are known maintenance & unknown additional costs like tires, brakes, "surprise" failures, AAA or other tow plan...

Some intangible considerations are: reliability in daily commutes, sentimental value, collectibility/ rarity, x/factor/ street cred, joy (or sorrow ha-ha) during use, etc.

Adding above, compare to the cost of new, typically a few $100 monthly for 3-5 years - vs. - your root repair scenario of $7.50 monthly (plus other expense) for 10 years. Usually we're in a better financial position by doing what's considered normal maintenance (that even new stuff eventually needs somehow).

(C)
If a commuter, to avoid headaches, maybe consider selling as is and picking up a low mile late model or new bike that has a good reliability reputation.

Sleep on it before hammering things out, you'll feel better.

Hope this helps!
 

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Is it worth going through the pain/price of gaskets to remove the next cover to check the sprag
+1 to get the sprag off and inspect it, it's not a difficult job. Locking the sprag can be a pain but it can be done. I've re-used paper gaskets plenty in the past without issues as long as they come off whole.

Also in the below image, some part of the cover is missing - but found it missing in some pics online too (Sprag (Starter) Clutch) - is that just cosmetic?
That's normal, nothing to worry about.
 
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