Author Topic: jumping chain  (Read 1502 times)

Offline derek taylor

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jumping chain
« on: 20.04. 2014 19:56 »
had a run out yesterday flash run well until coming home, stopped at some lights going up hill wife on the back when we set off the bike jerked twice as if the rear chain jumped teeth.
the chain does seem a bit slack, but if that's not the problem what else could it be ?

Offline Topdad

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Re: jumping chain
« Reply #1 on: 20.04. 2014 20:32 »
Hi derek, was the chain  loose without either of you on board ? Or just with you ? I think two up that could make it looser. what are the teeth like and the condition of the chain. Just adjust the chain and try it then decide what do do, regards bob
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Online muskrat

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Re: jumping chain
« Reply #2 on: 20.04. 2014 21:02 »
Could it be the cush drive jumping? If so you both need to lose weight *eek*.
Cheers *smile*
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Offline derek taylor

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Re: jumping chain
« Reply #3 on: 20.04. 2014 21:15 »
had a quick look tonight chain is a bit slack wile an center stand

Online Brian

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Re: jumping chain
« Reply #4 on: 21.04. 2014 00:19 »
Derek the chain will be loose while the bike is on the centre stand. There is a thread here that deals with how to adjust your chain.

You need to have the bike sitting on its wheels and get someone to sit on the pillion seat and then check the chain, it tightens as the suspension compresses.

If the chain was jumping while you where riding the bike the chain would have to be horribly loose or the sprockets totally worn out.

You also need to check the cush drive, it can not actually jump unless it has come loose and if that is the case it needs fixing immediately.

Offline derek taylor

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Re: jumping chain
« Reply #5 on: 21.04. 2014 07:16 »
was ok when riding jumped when we set off

Online BSA_54A10

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Re: jumping chain
« Reply #6 on: 21.04. 2014 09:22 »
Checked the primary chain reciently ?
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Offline wilko

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Re: jumping chain
« Reply #7 on: 21.04. 2014 22:58 »
Broken driveshaft on the crank  or sheared keyway on mainshaft.

Online bsa-bill

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Re: jumping chain
« Reply #8 on: 22.04. 2014 10:48 »
Quote
Could it be the cush drive jumping? If so you both need to lose weight

or the cushdrive nut is bidding farewell and adieu to it's neighbours  *conf*
All the best - Bill
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1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline derek taylor

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Re: jumping chain
« Reply #9 on: 22.04. 2014 20:13 »
have added a pick to first thread

Online bsa-bill

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Re: jumping chain
« Reply #10 on: 22.04. 2014 21:07 »
Good one, that looks all in reasonable  order
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online WozzA

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Re: jumping chain
« Reply #11 on: 23.04. 2014 05:34 »
Wheel spin ????   *????*
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Offline wilko

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Re: jumping chain
« Reply #12 on: 24.04. 2014 00:05 »
Checked the primary chain reciently ?
   I allus have one at eleven!

Offline derek taylor

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Re: jumping chain
« Reply #13 on: 28.04. 2014 19:32 »
just been thinking its only done it since i fitted the new clutch plates.

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Re: jumping chain
« Reply #14 on: 28.04. 2014 21:21 »
G'day Derek.
Other things to check. Primary sprocket alignment and clutch basket bearing wear. Under load like you described the basket could cock off a bit causing momentary slip.
Cheers
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