bobtlr Posted November 20, 2007 Report Share Posted November 20, 2007 Hey, a mate's sherco doesn't run verry nice any more (it used to do) it stil has a lot of power and revs high but on half trothle it sputters a bit, also when revving it it doenst sounds as sweet as it should. At full tilt it seems ok. The bike is fitted with an keihin carb done by the importer in the Netherlands. The bike is used weekly on an intermediate level, air filter is cleaned every time. fuel oil mix is ok, new sparkplug does'nt help. I wonder if it could be the exhaust (first part of the exhaust is cleaned regulary) or mayby the seals on the crankshaft. Any other sugestions? regards bob sorry for the spelling mistakes i am not used to write in English Quote Link to comment Share on other sites More sharing options...
wrc Posted November 20, 2007 Report Share Posted November 20, 2007 Hey,a mate's sherco doesn't run verry nice any more (it used to do) it stil has a lot of power and revs high but on half trothle it sputters a bit, also when revving it it doenst sounds as sweet as it should. At full tilt it seems ok. The bike is fitted with an keihin carb done by the importer in the Netherlands. The bike is used weekly on an intermediate level, air filter is cleaned every time. fuel oil mix is ok, new sparkplug does'nt help. I wonder if it could be the exhaust (first part of the exhaust is cleaned regulary) or mayby the seals on the crankshaft. Any other sugestions? regards bob sorry for the spelling mistakes i am not used to write in English Hi What mix ratio are you running on, and what two stroke oil are you using? Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted November 20, 2007 Report Share Posted November 20, 2007 Hi What mix ratio are you running on, and what two stroke oil are you using? Put the dellorto back on and start from there. 33 pilot 118 main you're away. Quote Link to comment Share on other sites More sharing options...
bobtlr Posted November 21, 2007 Author Report Share Posted November 21, 2007 Hi What mix ratio are you running on, and what two stroke oil are you using? i have no idea its not my bike (i drive 4 stroke machine) but i thought GRO 2 stroke oil Quote Link to comment Share on other sites More sharing options...
bobtlr Posted November 21, 2007 Author Report Share Posted November 21, 2007 (edited) Put the dellorto back on and start from there. 33 pilot 118 main you're away. But it used to run fine on the keihin, the bike has never been used with a dellorto carb. (it is a common mod here they even charge more for a new bike fitted whit a keihin, they do it on gas gas bikes also) It looks to me that it's a problem thats starts at a certain moment and gets worse by time, the bike is used a lot mayby even the piston that's used. Has someone already changed the exhaust on his bike for a new one? Does it make a big diference? regards bob Edited November 21, 2007 by bobtlr Quote Link to comment Share on other sites More sharing options...
wrc Posted November 21, 2007 Report Share Posted November 21, 2007 But it used to run fine on the keihin, the bike has never been used with a dellorto carb. (it is a common mod here they even charge more for a new bike fitted whit a keihin, they do it on gas gas bikes also) It looks to me that it's a problem thats starts at a certain moment and gets worse by time, the bike is used a lot mayby even the piston that's used. Has someone already changed the exhaust on his bike for a new one? Does it make a big diference?regards bob Go onto the Sherco websites and you can download the manuals.........and tech info.........nothing to loose........but i use the oil they recommend. Its very good and the bike cleans out well Quote Link to comment Share on other sites More sharing options...
ham2 Posted November 22, 2007 Report Share Posted November 22, 2007 (edited) My 290-05 had/has?(I'm still rebuilding it) a similar problem,the low revs/idle performance was erratic,it didn't splutter like yours but I know it could run a lot better low down. I'm presuming that you wash out and clean your carb' and filter as a routine. Here's a list of work(in order of complexity and cost )that I have carried out whilst fault chasing:- 1)Took off the carb' spacer plate.....very little difference.-Cost Edited November 22, 2007 by HAM2 Quote Link to comment Share on other sites More sharing options...
bobtlr Posted November 22, 2007 Author Report Share Posted November 22, 2007 My 290-05 had/has?(I'm still rebuilding it) a similar problem,the low revs/idle performance was erratic,it didn't splutter like yours but I know it could run a lot better low down.I'm presuming that you wash out and clean your carb' and filter as a routine. Here's a list of work(in order of complexity and cost )that I have carried out whilst fault chasing:- 1)Took off the carb' spacer plate.....very little difference.-Cost Quote Link to comment Share on other sites More sharing options...
dabomb Posted November 22, 2007 Report Share Posted November 22, 2007 Has the engine been taken apart before this fault started?? Quote Link to comment Share on other sites More sharing options...
ham2 Posted November 23, 2007 Report Share Posted November 23, 2007 Has the engine been taken apart before this fault started?? dabomb, if you mean my bike then ..no..I remember the previous owner denying any motor problems( I have no need to doubt the lad)and judging by the corrosion on the bolt threads I think they were last put in--bone dry-- Sherco factory style!. Ok? Quote Link to comment Share on other sites More sharing options...
dabomb Posted November 23, 2007 Report Share Posted November 23, 2007 dabomb, if you mean my bike then ..no..I remember the previous owner denying any motor problems( I have no need to doubt the lad)and judging by the corrosion on the bolt threads I think they were last put in--bone dry-- Sherco factory style!.Ok? Sorry ham 2,i was replying to the fist post(bobtlr).The reason i ask,is because i had a similar problem my self regarding the spluttering etc.The previous owner of my bike(sherco 290) had replaced the piston,but putit in the wrong way round(believe it or not),took a mechanic to find it because the the guy i bought it off said he had never touched the engine,so i never looked for that sort of problem. If you read this bobtlr,best way to check is remove the front pipe then crank the engine over,make sure the bottom of the piston doesnt come above the bottom edge of the port. Quote Link to comment Share on other sites More sharing options...
bobtlr Posted November 23, 2007 Author Report Share Posted November 23, 2007 Sorry ham 2,i was replying to the fist post(bobtlr).The reason i ask,is because i had a similar problem my self regarding the spluttering etc.The previous owner of my bike(sherco 290) had replaced the piston,but putit in the wrong way round(believe it or not),took a mechanic to find it because the the guy i bought it off said he had never touched the engine,so i never looked for that sort of problem.If you read this bobtlr,best way to check is remove the front pipe then crank the engine over,make sure the bottom of the piston doesnt come above the bottom edge of the port. Hey, as far as i know the engine as'nt been open yet, but i will check it the way you describe. The bike ran well in the beginning but now its not that good anymore, so i think mayby some component that's worn out? bike is now 2,5 years old and is used intensive. what should i look for first? piston, carb exhaust,... regards bob thanks for all the tips Quote Link to comment Share on other sites More sharing options...
ham2 Posted November 23, 2007 Report Share Posted November 23, 2007 Thanks for the tips,the owner of the bike is a mate so i am not sure what he did on it but he takes good care of the bike, filter gets cleaned out in time oil changes etc. i'll give him your tips so he can try them . let me know if your bike improves with the new bearings and seals please. regards bob Newsflash 18.50hrs..just tried my new bearings and seals in the street.......and....... success...bottom end torque restored,idle much more consistent.. This is the only remedy that has shown any positive results for my particular bike...Good luck Quote Link to comment Share on other sites More sharing options...
bobtlr Posted November 27, 2007 Author Report Share Posted November 27, 2007 hey thanks for the confirmation, i will pass all the tips to my mate regards bob Quote Link to comment Share on other sites More sharing options...
alan bechard Posted November 28, 2007 Report Share Posted November 28, 2007 The exhaust can make a difference. We are fortunate in that I have other bikes to swap around suspect peices on too see where the problem lies. If say you took your exhaust and swapped it with your freind, and then his bike ran bad, and yours ran fine, you would be fairly certain you had the problem. This kind of thing, I usually try and start at the basics, and slowly proceede forward. Clean new fuel, clean air filter, clean carb, careful inspection for air leaks, new spark plug, etc. etc... Then look for the freind with the same bike and start stealing parts Good luck, hope you guys find it and fix it. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.