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Author Topic: front pulley drive failure  (Read 850 times)

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Offline cjscr

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front pulley drive failure
« on: September 26, 2021, 09:12:49 pm »
2017 scr950 18107 miles changed the oil and plugs and cleaned the air filter moving the bike around the driveway it made a lot of noise out of the front pulley. pulled all covers red dust on belt covers, rub marks on top belt cover, metal shavings in pulley cover, and when i put it in 1st gear and yank the bike the front pulley makes a knocking noise and shifts around? i know i'm rough on things but damn i didn't expect this kind of problem. no oil leaks.

fuck me metal shavings?



Offline cjscr

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Re: front pulley drive failure
« Reply #1 on: September 26, 2021, 10:41:26 pm »
headed out to the store and the drive totally failed, won't grab in any gear it just slips. parked it in some dude's driveway that was kind enough to let me leave it there. walked then my brother picked me up. super glad i didn't try to ride to work tomorrow
« Last Edit: September 26, 2021, 11:46:31 pm by cjscr »

Offline lunkhead

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Re: front pulley drive failure
« Reply #2 on: September 27, 2021, 01:24:21 am »
Sounds like your nut came loose.
C-SPƎC

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Offline cjscr

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Re: front pulley drive failure
« Reply #3 on: September 27, 2021, 08:34:15 pm »
brought it home today, took apart the drive, the splines on the pulley and the output shaft of the transmission are gone.

Offline srinath

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Re: front pulley drive failure
« Reply #4 on: September 27, 2021, 09:09:26 pm »
That sucks. IMHO - get a new pulley made of steel and weld them together - stock is aluminum right - OMG, why did it shred the shaft then ? Is the stock front pulley steel ?

Cool.
Srinath.

Offline ShakerNorm

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Re: front pulley drive failure
« Reply #5 on: September 29, 2021, 08:06:18 pm »
Maybe the belt tension was wrong?

It sounds like the bearings for the shaft have failed (if the shaft moves around), and that's the only thing I can think of that could cause that kind of failure.
NOBODY hates winter more than a Canadian Biker!

Offline lunkhead

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Re: front pulley drive failure
« Reply #6 on: October 01, 2021, 11:48:23 am »
The red dust shouldn't be there with a tight pulley. It indicates the splines fretting like you might see on a floating spocket. It seems like the pulley had to be beating on the splines and fretting before it started chipping them away. Once the splines are gone, the direction of the output shaft could start trying to tighten the nut back up if it didn't fall off. Hope the OP doesn't leave us hanging. ???
C-SPƎC

Offline cjscr

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Re: front pulley drive failure
« Reply #7 on: October 01, 2021, 06:40:24 pm »
ordered a teardown manual and will go over it thoroughly before ordering parts. bike's in the garage

Offline ShakerNorm

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NOBODY hates winter more than a Canadian Biker!