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Winder
02-10-13, 06:47 PM
Old chain and sprockets done 20k miles and was jumping about lots so I have changed them.

New chain is on and jumps a little but nowhere near as bad as the old one. I can feel it jump when I'm riding.

•Bike is a 2005 SV650s
•Brand new chain and sprockets
•Chain tension is 35mm
•All chain links and rollers are free moving
•Oil level is bang on half way between F and E
•Cush rubbers in good nick
•Every nut torqued up
•Wheels aligned and chain running straight.

Think that's everything.
Could you advise on my next thing to check over?
Thanks

Video of jumping chain
http://youtu.be/JlvtHyiGLZA

Tomor
02-10-13, 06:49 PM
Coolant level / renew?

Winder
02-10-13, 06:54 PM
Coolant changed about 6k miles ago ish. Will check the service book.
How would that make the chain skip around?
Level is about 3mm below Full

Tomor
02-10-13, 06:58 PM
Oh, I though you were just stating that you had put a new C+S kit on and were asking what to do next in general. I don't know why the chain is still jumping. Try putting it on the 20mm side of tension and see if it still does it?

Bibio
02-10-13, 07:09 PM
that is perfectly normal while sat on a paddock stand in gear and at tickover or slight throttle.

punyXpress
02-10-13, 07:14 PM
Probably quite normal.
The V twin has firing impulses that are not evenly matched, so the chain is only 'driving' the back wheel part of the time. At low revs this would have the effect you can see and feel.
If you can follow this you're doing well!
I lost the plot on line two.
Best of luck.

DJ123
02-10-13, 08:13 PM
It's about to implode. Quite clearly it's a sign to get a new bike, something like a Tiger 800?

Viney
02-10-13, 10:11 PM
Correct chain and sprocket combo?

Did you buy separately or as a kit?

Never ever heard of this on a new chain. Never had this. My Bike has had a few chains over the years. Tighten chain a little more to see if it resolves it.
-------
Sent using the power of Moomins

wideguy
03-10-13, 12:32 AM
Looks a little slack to me. My manual says 20-30mm, and I always recheck after the first ride. Chains commonly get a little longer after they've been run in.

Winder
03-10-13, 07:20 PM
Still does it at 20mm. I have always kept SV chain at 30/35mm of play but can't say I ever noticed it jumping about like this before on any of my bikes.

Chain and sprockets correct match, matched up with the ones I took off too although obviously the old ones were very worn.

I'll just keep an eye on it. If people say its normal and they have this jumping also then I'm not that bothered.

Lawman
03-10-13, 07:23 PM
Are you sure it's the chain and not some gearbox issue, etc, doesn't sound right at all to me.

Winder
03-10-13, 07:28 PM
When I get a spare few minutes I will put it up on the stand and go through the gears to see it it still does it.
I'm sure it's jumping about a bit in all gears when riding but may just be in my head.
Also not sure if rolling on throttle cures it or not as it doesn't feel jumpy under acceleration, or not as jumpy.

Bibio
03-10-13, 07:31 PM
it's caused by backlash in the gearbox components. both my SV's have always done it even a brand spanking new one just out the crate.

you have a problem if you can feel a pulse while riding and usually indicates a tight spot in the chain.

Bibio
03-10-13, 07:33 PM
might be your riding as v-twins don't like low revs. try keeping the revs up a bit even if you have to drop a gear.

wideguy
03-10-13, 07:59 PM
might be your riding as v-twins don't like low revs. try keeping the revs up a bit even if you have to drop a gear.
v-twins usually make considerable torque at low rpms. I find them working comfortably at much lower revs than in-line 4's, and my '00 SV650 is happy at 3,000, doesn't really complain even at 2,500.

How many miles have you put on the chain? And what brand is it. About 2 years ago I put an RK chain on my SV. It was very tightly made, stayed kinky for 1,000 miles, then relaxed, gradually stretching to it's actual design operating length. I was unhappy and won't buy another RK for quite a while. It did the same thing yours is doing when run on the paddock stand, otherwise, OK, though I got about 5,000 miles fewer than usual out of it.

Winder
03-10-13, 08:19 PM
might be your riding as v-twins don't like low revs. try keeping the revs up a bit even if you have to drop a gear.

I change up between 5k-7k rpm most journeys. If I go out for a spin I'll rev it higher.
30-40 limits I'm usually in 2nd or 3rd
40-50 limits 3rd or 4th
50-80 4th or 5th

If that's changing up too early I best get better ear plugs

Winder
03-10-13, 08:21 PM
Only 200 miles on the chain.
DID O-ring with JT steel sprockets bought as a "kit" from wemoto

wideguy
03-10-13, 08:30 PM
I've never had a problem with DID chains.
Is it kinky anywhere when just sitting? Is it tighter in one location, and looser in another, as in, check the tension at various places?

wideguy
03-10-13, 08:38 PM
I change up between 5k-7k rpm most journeys. If I go out for a spin I'll rev it higher.
30-40 limits I'm usually in 2nd or 3rd
40-50 limits 3rd or 4th
50-80 4th or 5th

If that's changing up too early I best get better ear plugs
Riding on the roads, I usually plonk along lazily in high gear or fifth. Our usual pace is around 65 mph, slower when necessary. Even tight hairpins up and down the mountains, I mostly use 4th and 3rd, rarely rev above 7,000, usually not above 6,000. I try to be smooth and keep my corner speed up. The SV makes it easy.
I bet I get better fuel economy than you do, and use less oil too. Not that that's what my fun is about...

Bibio
03-10-13, 09:13 PM
nope not your riding.

The Idle Biker
03-10-13, 10:12 PM
Can someone confirm if Winder has spent money without needing to?

(Yes is the preferred answer.)

Winder
03-10-13, 10:20 PM
That has never happened Laurie

Sid Squid
04-10-13, 08:35 AM
Can someone confirm if Winder has spent money without needing to?
(Yes is the preferred answer.)
If the exact same phenomenon is exhibited with this and the last chain, then yes. Of course the old chain may have been worn out, but, if worn relatively evenly, (note; relatively - chains and sprockets rarely wear perfectly consistently), then even at the end of its life this 'problem' will not have been caused by the chain per se.
An engine never turns perfectly evenly, the firing pulses are a finite distance apart, thus the engine slightly speeds up with each pulse and similarly slows down between them, the slower the engine speed the greater the interval between pulses, and obviously the reverse is also true, thus the force applied to the chain as the engine turns is not consistent and this is most noticeable at tickover.

punyXpress
04-10-13, 09:31 AM
. . . and is FAR more noticeable with a V-twin ( or a single )

Winder
04-10-13, 10:26 AM
20k miles and a front sprocket with shark fin shaped teeth I think it was due a change

Sid Squid
04-10-13, 10:31 AM
. . . and is FAR more noticeable with a V-twin ( or a single )
Precisely so. The fewer the cylinders the further apart the pulses at any given engine speed. That's why, mostly, big motors with lots of cylinders - 8 or more - are so silky smooth, the pulses are closer together thus the cyclic acceleration and deceleration of the engine is less apparent.

wideguy
04-10-13, 07:53 PM
2800 cubic inch (roughly 45,900cc) 18 cylinder twin row radials are so smooth they can blow one cylinder right off the crankcase and nobody will notice until they see it missing.