adam1 Posted January 1, 2012 Report Share Posted January 1, 2012 Happy new year all Just a quick couple of questions, I have freshened my bike up over winter, with some new parts etc ready for the new season, and need a few things pointing out. 1. My mate has just bought a 08 rev 3 250 and his seems to have more compression and feels more about it, both have fly wheel weights on but his noticeabley crisper, any idea's? is it time for a piston change? 2. Also I turned my tyre round to get abit more life out of the tyre and fitted a new shock guard rubbe flap, I have put the wheel back on and now for some reason the rear wheel is nearly touching the swingarm and the rubber flap has worn after three trials. The chain is the same? Any ideas?? I might be being thick and if so point it out nicely! Ha Cheers all Adam Quote Link to comment Share on other sites More sharing options...
chewy Posted January 1, 2012 Report Share Posted January 1, 2012 Could be ignition timing ,carburation..re rubber flap either swing arm shrunk or chain different tension or thats why the original was worn out. Quote Link to comment Share on other sites More sharing options...
lineaway Posted January 1, 2012 Report Share Posted January 1, 2012 If you have a `07 and his was an `08 that is why. The `08 ran better. Now turnin` the tire trick is only the fresher nobs are now closer to the rubber? Quote Link to comment Share on other sites More sharing options...
paul w Posted January 2, 2012 Report Share Posted January 2, 2012 08 better carb. rubber flaps last 3 trials at best. i did buy some rubber that was thicker and cut my own. a piston and rings might be worth the investment if your bikes done a fair bit of work. Quote Link to comment Share on other sites More sharing options...
adam1 Posted January 2, 2012 Author Report Share Posted January 2, 2012 Could be ignition timing ,carburation..re rubber flap either swing arm shrunk or chain different tension or thats why the original was worn out. Thought it could be ignition timing, just wondered if anyone had any pics of what to look for, carb wise it seems to run fine, might take carb off and clean jets etc, does any one have any standard carb settings to check against? The rear tyre does seem close like the chain is tensioned to much or to short, don't think swing arm shrunk! Ha ha. I am sure it hasn't always been like that, anyone no how many links the chain should be and how should the chain be tensioned ie chain block 25mm from swing arm? Also what's the srandard gearing? Mines 11/42? Cheers Adam Quote Link to comment Share on other sites More sharing options...
adam1 Posted January 2, 2012 Author Report Share Posted January 2, 2012 If you have a `07 and his was an `08 that is why. The `08 ran better. Now turnin` the tire trick is only the fresher nobs are now closer to the rubber? I thought it just gave you a new edge? Thus giving better grip? Cheers adam Quote Link to comment Share on other sites More sharing options...
adam1 Posted January 2, 2012 Author Report Share Posted January 2, 2012 08 better carb. rubber flaps last 3 trials at best. i did buy some rubber that was thicker and cut my own. a piston and rings might be worth the investment if your bikes done a fair bit of work. I heard the 08 carb was better, I may put a new piston in soon, what's the best/easiest way of checking?, the rubber flap should last years it's only worn so quick cos it's touching the rear tyre, my mates don't? Adam Quote Link to comment Share on other sites More sharing options...
overdale Posted January 2, 2012 Report Share Posted January 2, 2012 Regarding the tyre touching the mudflap, it is definitely not to do with the tyre but with the sprockets and chain. The REV-3 had limited tyre clearance originally and flaps/shock absorber bottoms were scuffed. The clearance seems adequate when stopped, but when spinning, centrifugal force distorts the tyre profile so closing the gap! I would think that standard gearing would be 11/41 but you can check on the Beta UK website under the technical specification of your bike. If you have larger front or rear sprockets with a standard chain the gap will be smaller to get the correct tension. If you sprockets are correct, just get a half link -which is actually 1.5 links with 2 split links. This lengthens the chain enough for clearance and correct chain adjustment -this was definitely the case with Rev-3 200s where they used 11/42 sprockets. Performance wise, compression comes down to rings, if it doesn't rattle a lot, the piston is most likely ok but maybe some new rings would help. hope this helps Quote Link to comment Share on other sites More sharing options...
adam1 Posted January 2, 2012 Author Report Share Posted January 2, 2012 Regarding the tyre touching the mudflap, it is definitely not to do with the tyre but with the sprockets and chain. The REV-3 had limited tyre clearance originally and flaps/shock absorber bottoms were scuffed. The clearance seems adequate when stopped, but when spinning, centrifugal force distorts the tyre profile so closing the gap! I would think that standard gearing would be 11/41 but you can check on the Beta UK website under the technical specification of your bike. If you have larger front or rear sprockets with a standard chain the gap will be smaller to get the correct tension. If you sprockets are correct, just get a half link -which is actually 1.5 links with 2 split links. This lengthens the chain enough for clearance and correct chain adjustment -this was definitely the case with Rev-3 200s where they used 11/42 sprockets. Performance wise, compression comes down to rings, if it doesn't rattle a lot, the piston is most likely ok but maybe some new rings would help. hope this helps Thanks for the reply, It doesn't seem to rattle really so maybe only the rings need doing? This will give it more go I suppose?. I will check the gearing now and post the results. My mates does have 11/41 so that could account for the gap difference but 1 tooth would that make all the difference, prob about 1" extra gap? Cheers Adam Quote Link to comment Share on other sites More sharing options...
feetupfun Posted January 2, 2012 Report Share Posted January 2, 2012 Thanks for the reply, It doesn't seem to rattle really so maybe only the rings need doing? This will give it more go I suppose?. I will check the gearing now and post the results. My mates does have 11/41 so that could account for the gap difference but 1 tooth would that make all the difference, prob about 1" extra gap? Cheers Adam Chain and sprocket wear means that it is not just which sprockets you have that determines clearance. Just look at where the axle is in the slot. If it is at the front end of the slot you will have flap problems. If it is at the front end of the slot, add a one-and-a-half link to your chain to get more clearance. The axle will also need to be moved rearwards as the sprockets and chain wears with use. Quote Link to comment Share on other sites More sharing options...
mb4807 Posted January 5, 2012 Report Share Posted January 5, 2012 Standard gearing is 11-41 and chain length is 104 links I believe. And I think the chain tensioner should be 20mm from the bottom of the swing arm for correct adjustment. Quote Link to comment Share on other sites More sharing options...
pindie Posted January 5, 2012 Report Share Posted January 5, 2012 if it helps I have an 07 200 rev3. It is on 11.42 gearing. It also has two split links. I thought someone had been fiddling with a broken chain. After reading all of this it is a obvious reason for the two links. Or is it a 1.5 link...? Quote Link to comment Share on other sites More sharing options...
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