# Le Champion SL - Throwing Chain



## matamua (May 2, 2008)

Hey everybody. I just got a Motobecane Le Champion SL for my birthday. I took it out for it's maiden voyage, but it didn't last too long. I shifted into the big ring and down into the smallest cog (not simultaneously of course) and went down to the drops for the downhill.

I started pedaling and it threw the chain off the big ring. I checked the limit screws and everything seems to be fine. It only seems to happen under load. Does anyone have any ideas as to what is going on?

Also, the rings have hardly any wear on them, but it seems like they have a little bend in them. I'm not sure how to describe it, but it seems as to be out of "true" in one spot. In the little ring and biggest cog, every revolution, the chain hits the inside of the front derailleur cage, but only in one spot. Then, in the smallest cog and big ring, it hits the outside of the cage. Any suggestions?


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## Lifelover (Jul 8, 2004)

Post a pic of the chainring. However, I don't think that will be the problem.

Sounds like a FD limit issue even though you said you checked that. Adjust it "in' a little and see if that helps.


No reason you can't shift front and rear at the same time as far as I know.


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## RC28 (May 9, 2002)

Item #1: Front derailleur might be mounted a bit too high.

Item #2: Yes, chainrings sometimes get bent. Get something with some leverage and bend them back (adjustable wrench or something)...

Now that I think about it, the out of true chainrings might be assisting in dropping your chain...if the spot where it is out of true sways to the outside.

Hope this helps...


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## 20sMotoSpirit (May 27, 2007)

Also, the Moto SL is a Compact Chain ring.... 50/34 and even 50/36 are pushing the limits to what shifting can offer for systems built for the 50+ rings. Thats why FSA usually offers custom derailuers for their cranks.

I just ordered mine too about 5 hrs ago. BTW which color did you get?.. pics?


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## matamua (May 2, 2008)

RC28 - I checked the limits again and looked at the derailleur height. The derailleur height was off by about 3mm, and I fixed that. I also spent about two hours "truing" the chainrings. It was a pain, but it seems to have worked for now. 

I took it out and bombed the hill by my house at about 65km/hr and (big ring/smallest cog) it skipped and came off. The limits are correct, the height is correct. I think it's probably flex in the big ring, and possibly a bad tooth on the cog. Everything else seems fine though. Thanks for the help!


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## bikesdirect (Sep 9, 2006)

matamua said:


> RC28 - I checked the limits again and looked at the derailleur height. The derailleur height was off by about 3mm, and I fixed that. I also spent about two hours "truing" the chainrings. It was a pain, but it seems to have worked for now.
> 
> I took it out and bombed the hill by my house at about 65km/hr and (big ring/smallest cog) it skipped and came off. The limits are correct, the height is correct. I think it's probably flex in the big ring, and possibly a bad tooth on the cog. Everything else seems fine though. Thanks for the help!


I think I know the issue

Your crank is not seated correctly

best way to fix is remove crank arms; clean spindal
And re-install and tighten down with steel crank bolts [then replace bolts with alloy ones if that's what you have

if you need further help
please PM me
thanks
mike


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## Krsolutions (Jul 28, 2007)

bikesdirect said:


> I think I know the issue
> 
> Your crank is not seated correctly
> 
> ...


hey mike please check ur pm's .

I want a bike :thumbsup:


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