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The TTR250 FAQ web pages -> TTR250 -> Repairs and maintenance -> yet another sprag clutch question
Post Info TOPIC: yet another sprag clutch question
glynn4623


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yet another sprag clutch question
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hi all

I noticed recently whilst doing some work on the bike that when I turn the engine over manually(either by turning rear wheel or by turning flywheel bolt with a socket) that the starter motor turns aswell. my understanding is that the sprag clutch is there to stop the engine from turning the starter motor (if that makes sense)

since noticing this I have also noticed that with engine running you can hear the starter turning.(probably the reason why the starter brushes were worn out)

its always had the clunk when you cut the engine and because of this I have inspected the starter gears a few times and there is no wear and they all look like new.

now heres the confusing bit(for me anyway) I took the flywheel cover off and turned the flywheel whilst holding the starter gear  and it didn't seem to even try to turn the starter gear. also if I reach behind the flywheel and turn the big gear(the one the sprag is bolted to ) it turns really freely one way and locks solid the other way ( as it should).

   just wondering if anyone has any thoughts before I start stripping it down and splashing out on a new sprag

      thanks in advance glynn



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texasT


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Have you read

.... http://www.ttr250.com/Sprag_replacement/TTR_sprag_replacement.htm 

good stuff might help?

Greg



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'04 TT-R250sc Blue model U.S.A.
TTRfan


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A worn sprag can occasionally jam from the kickback on close down and no longer operate as a "one-way" clutch until it frees itself off.



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glynn4623


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thanks for the rply greg but I was wondering more about if anyone has noticed the starter motor turning with the engine as there is a lot about the clunk on cut off being related to a worn sprag but ive seen nothing on the sprag turning the starter as the engine turns??
I will be replacing the sprag anyway but thought that other peoples experience of this will help other people in the future
(erm kind of thing)

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glynn4623


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right so looking at the instructional about replacing the sprag I see that a FLYWHEEL PULLER is needed but it also says that the rear axle can be used is the absence of the flywheel puller. my question is HOW????
does anyone know how this is done or any other ways of removing it without the puller???


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TTRfan


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I have used the rear axle before but it's a PITA compared to using the pucca puller. Just screw it in tight and give it a tap on the end as you tighten it until the flywheel breaks off the taper.

Here's a pic of my mate Adrian using the axle:

axle_fwheel_puller016.jpg

Full article here 

 



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dern


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I found that the rear axle worked well for me but the inconvenience of having the remove the rear wheel would make having the actual tool a good thing. Basically you just clean off the threads, apply a little grease and wind it in and the flywheel will pop off. Don't lose the woodruff key.

Mark

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glynn4623


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ok cheers fellas I thought that's how it would work but best to make sure. just need a bolt the right size so as not to have to remove the rear wheel. im sure ill have one in the magic tub :)

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hanzo


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18x1.5 is what you need bolt wise .

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