trialsbikeadam Posted October 11, 2009 Report Share Posted October 11, 2009 (edited) I recently purchased a Sherco 2.9 2006, the bike has ran well for the past month and a half i've owned it until two weeks ago. It's becoming almost impossible to start when warm after it sits for 5-10 minutes not running (walking a section or waiting to ride a section with the bike off) Cold it will start fine, if it's warm and you shut it off and immediately restart it it's fine. It's only when it sits and "soaks" while hot ,it doesn't want to restart. Last week at an event i actually had Ryan Young trying to help me start this thing so i could ride the section! The plug,carb,fuel ect. are all workin properly and have been switched/cleaned multiple times, the bike runs fine, when running, just don't shut it off lol. I'm grasping for straws here so any input or suggestions any one has would be greatly appreciated, Thanks, Adam I have also disconnected the kill switch to elimate it as a problem Edited October 11, 2009 by Trialsbikeadam Quote Link to comment Share on other sites More sharing options...
copemech Posted October 11, 2009 Report Share Posted October 11, 2009 I recently purchased a Sherco 2.9 2006, the bike has ran well for the past month and a half i've owned it until two weeks ago. It's becoming almost impossible to start when warm after it sits for 5-10 minutes not running (walking a section or waiting to ride a section with the bike off) Cold it will start fine, if it's warm and you shut it off and immediately restart it it's fine. It's only when it sits and "soaks" while hot ,it doesn't want to restart. Last week at an event i actually had Ryan Young trying to help me start this thing so i could ride the section! The plug,carb,fuel ect. are all workin properly and have been switched/cleaned multiple times, the bike runs fine, when running, just don't shut it off lol. I'm grasping for straws here so any input or suggestions any one has would be greatly appreciated, Thanks, Adam Are you running AVGAS? Quote Link to comment Share on other sites More sharing options...
chewy Posted October 11, 2009 Report Share Posted October 11, 2009 Possibly crank seals air leak, no nothing about shercos may be electrical insulation problem Quote Link to comment Share on other sites More sharing options...
trialsbikeadam Posted October 11, 2009 Author Report Share Posted October 11, 2009 Sorry, but i'm unsure about "AVGAS" it is running a mixture of VP 110 and 93 pump fuel. It previosly had run on the 110 only but with switching the fuels in, out, and around i've dropped it to about 70/30 blend towards pump gas to reduce costs. Is there anyway to tell if there is an air leak from the crank seals? Wouldn't an air leak cause high idle/lean air fuel mixture? It doesn't seem to have any of those symptoms and while kicking it feverishly you begin to smell fuel. I also know nothing of the electrical system, the headlight and handlebar switches have all been deleted by an unknow, so tracing the wiring is a scary proposition since i don't now the original design. Thanks for your suggestions and any further input would again be appreciated. Thanks, Adam Quote Link to comment Share on other sites More sharing options...
copemech Posted October 11, 2009 Report Share Posted October 11, 2009 Try just running straight 93 pumpgas. No need for the race fuel. Quote Link to comment Share on other sites More sharing options...
zippy Posted October 11, 2009 Report Share Posted October 11, 2009 I run 93 octane in my 2000 2.9, And I know my brother's 2003 2.9 will NOT run on race gas, only takes 93 octane. One of the reasons I like the Shercos.........Fuel is cheaper to run it. Quote Link to comment Share on other sites More sharing options...
trialsbikeadam Posted October 11, 2009 Author Report Share Posted October 11, 2009 Thanks! I will try straight 93 but it has run off the 110 with no problems. A NEW DEVELOPMENT though is it leaking oil from the crankcase breather, it did this when i first purchased the bike (month and a half ago) and after working the dealer i purchased it from (tec cycles) we found it to be 50cc over filled and it stopped the leak, atleast temporarly. It's leaking slowly enough it would take a week or so to drain it. I read the post on this being caused by leaking crank seals or center gasket and to check by submersing the vent tube in water to check for bubbles, I tried this with no bubbles as a result? but is still leaking oil. Drained and refilled, no "extra oil" in there and when refilled with 430cc just to be sure it's still pushing it out. Could this crank seal issue also be the cause of the intermentant hard starting? Thanks guys for all your help Quote Link to comment Share on other sites More sharing options...
stork955 Posted October 11, 2009 Report Share Posted October 11, 2009 Gday, you have a common issue. You need to crack the throttle slightly while starting the bike in this condition. The reason is that after a short "soak" heat from the engine begins to evaporate fuel in the carb bowl, causing an over-rich mixture which sits there until it dissipates or you try to start the bike. Holding the throttle slightly open weakens this mixture slightly by allowing more air in, so restoring balance. Its the same as the hot start systems people buy for the 4 stroke moto crossers etc but you do it yourself for no money. The amount you need to open the throttle will vary but you will find this out through trial and error. About 5mm on the grip will be a good place to start. Cheers, Stork Quote Link to comment Share on other sites More sharing options...
trialsbikeadam Posted October 11, 2009 Author Report Share Posted October 11, 2009 Thanks I'll give that a try! The oil leak has also remadied itself for whatever reason again I've only owned this thing for just over a month and the sherco's sure do seem to have a lot of quirks to them, from the crazy air filter design and ritual to wash the bike to this new development. Anyone intersted in buying a sherco Quote Link to comment Share on other sites More sharing options...
zippy Posted October 11, 2009 Report Share Posted October 11, 2009 Trialsbikeadam Posted Today, 04:23 PM Thanks I'll give that a try! The oil leak has also remadied itself for whatever reason again huh.gif I've only owned this thing for just over a month and the sherco's sure do seem to have a lot of quirks to them, from the crazy air filter design and ritual to wash the bike to this new development. Anyone intersted in buying a sherco biggrin.gif I am interested!!! But my MRS. is NOT. Quote Link to comment Share on other sites More sharing options...
trialsbikeadam Posted October 11, 2009 Author Report Share Posted October 11, 2009 The ever so slight throttle opening does seem to help! but you have to be precise with it, too little and nothing,too much and nothing. I'll keep playing around the yard with it to verify but i hope it's really this simple and easy! Thanks everyone for your suggestions and i'll repost with an update or if problems persist. If you can talk the MRS. into it i'm seriously considering selling this thing and sticking with the KTM for the winter Quote Link to comment Share on other sites More sharing options...
htrdoug Posted October 12, 2009 Report Share Posted October 12, 2009 (edited) The ever so slight throttle opening does seem to help! but you have to be precise with it, too little and nothing,too much and nothing. I'll keep playing around the yard with it to verify but i hope it's really this simple and easy! Thanks everyone for your suggestions and i'll repost with an update or if problems persist. If you can talk the MRS. into it i'm seriously considering selling this thing and sticking with the KTM for the winter Stick with it there Adam!It can surely be cured! I always try to do a pressure test of any twostroke that acts funky,best to be reassured about the sealing of the engine before chasing problems on a bike that has ran fine before. You should carry a test spark plug with you that is gapped out wider than spec (about .100) and just pop that into the end of the plug wire the moment it fails to start to verify it'll jump that extra gap(takes more spark to light a plug inside a engine under compression is the reason for the extra gap)I like to fix a pigtail wire to the plug with an aligator clip on it so that I have a reliable ground connection. If spark is wonky then clean all ground connections very well before spending moolah on parts! You might try raising the idle setting just a bit so that you don't need to try to judge the throttle opening but that sounds like a stopgap cure. Make damn sure your pump gas has no alcohol in it. I'd check float height too. I went riding with TI guys Jim Z,Doug Hodgdon,Bill Super,and a couple of other guys down in Bedford today,Bill hurt his leg right off the bat and had to bail,and the rocks were OMG slick so we couldn't try much,but my old Fantic was going along just fine,tried much more stuff than the Vintage lines at the TI events,but then my clutch cable broke,gonna have to carry spares I guess.Pulled the front brake cable apart at Stoney,I ridden motorcycles for forty freakin' years and haven't broke but five or six over that amount of time Edited October 12, 2009 by htrdoug Quote Link to comment Share on other sites More sharing options...
copemech Posted October 12, 2009 Report Share Posted October 12, 2009 Thanks I'll give that a try! The oil leak has also remadied itself for whatever reason again I've only owned this thing for just over a month and the sherco's sure do seem to have a lot of quirks to them, from the crazy air filter design and ritual to wash the bike to this new development. Anyone intersted in buying a sherco Sherco's ARE THE EASIEST to work on and maintain! Get off the race gas thing, be sure your pilot jet is about 36-38 range! Hell, race cars and airplanes will not even HOT start on that stuff! Be sure your fuel inlet line is not up against the muffler, preheating your fuel! Be sure your gearbox vent tube is run under the intake, then up over and between the fuel(banjo) inlet and the carb, then back down to skidplate. Be sure to lean the bike over to about 45 deg when changing oil so you get it all out. Makes less puddles on the skidplate too, and I can target a 2L pop bottle cut down! The gearbox will find it's own level. Cases like 2K8's bike are unique, it is a WTC riders 125, then on to him. It has been run hard! If you get the bike really muddy or dirty, it takes less than one minute at the carwash to remove 4 screws, pull rear fender and air filter, stick (closed cell) foam block in AF hole and plug muff! BLAST AWAY! Another few seconds and you can yank the tank and block fuel line, clean everything! Chances are, everything is fine! Don't freak out, just stick to the program! Simple really! Quote Link to comment Share on other sites More sharing options...
trialsbikeadam Posted October 12, 2009 Author Report Share Posted October 12, 2009 HTRDOUG- Glad to see you're on here! Sorry to hear about the fantic going down but man i bet it was fun to ride with Jimmy Z and those guys! I've been wanting to get out and ride with them myself! I know the sherco's engine is tight, it just got a new cylinder (broken off bolt from header pipe) and all the internals checked (top end) I like that spark suggestion though it can't be too hard to carry an extra plug around. Are you going to try and make the T.I. event this weekend in tippecanoe? COPEMECH- bike is on straight 93 now and my fuel line IS right up against the muffler, is there any way to solve this? I've wrapped the line in a spring and bent the spring to allow for the utmost clearance but there's not much i can think to do around the carb fuel inlet, there's just not much space. I had read on the one posting about rerouting the crankcase breather and have done so, it still dripped out for a bit, but shortly stopped, to why i can't say though I always lean the bike when changing the oil (which i have done more than i should've considering i've owned this thing 6 weeks) The leak that started yesterday, appeared after a week old oil change and 3-4 hours on the bike so it wasn't immediatley after an oil change and just "self leveling". I changed it yesterday just to make sure no "extra oil" had gotten in there and after the change and the vent hose re-route, it still leaked then stopped? I'll look into the pilot jet tonight and see what I have in there but it should absolutely be between a 36-38? If not, change it correct? As for the air box design, well i won't go there catchers mitt is the first thing that comes to mind LOL. Thanks again for all your help trying to solve this problem, there are multiple (3-5) cases on the RYP forums i stumbled across last night with the same problem, most have never been resloved or just chalked up as "one of those things you learn to live with" So i do appreaciate all the time spent towards correcting this. Thanks, Adam Quote Link to comment Share on other sites More sharing options...
htrdoug Posted October 12, 2009 Report Share Posted October 12, 2009 Not gonna make tippecanoe event,had plans for the upcoming weekend for quite awhile,might make the last event though,we'll see. Now I'm very hot to get a Modern bike after riding with those guys,but I have to wait a bit since I spent this years moto money on a LC4e Dual Sport. How far are you from Bloomington?We're building some trials sections and a endurocross course just west of there over this coming winter just west of town and have been going out there on wednesday evenings to work it,but we'll be switching to weekends once we lose the afternoon light. HTRDOUG- Glad to see you're on here! Sorry to hear about the fantic going down but man i bet it was fun to ride with Jimmy Z and those guys! I've been wanting to get out and ride with them myself! I know the sherco's engine is tight, it just got a new cylinder (broken off bolt from header pipe) and all the internals checked (top end) I like that spark suggestion though it can't be too hard to carry an extra plug around. Are you going to try and make the T.I. event this weekend in tippecanoe?COPEMECH- bike is on straight 93 now and my fuel line IS right up against the muffler, is there any way to solve this? I've wrapped the line in a spring and bent the spring to allow for the utmost clearance but there's not much i can think to do around the carb fuel inlet, there's just not much space. I had read on the one posting about rerouting the crankcase breather and have done so, it still dripped out for a bit, but shortly stopped, to why i can't say though I always lean the bike when changing the oil (which i have done more than i should've considering i've owned this thing 6 weeks) The leak that started yesterday, appeared after a week old oil change and 3-4 hours on the bike so it wasn't immediatley after an oil change and just "self leveling". I changed it yesterday just to make sure no "extra oil" had gotten in there and after the change and the vent hose re-route, it still leaked then stopped? I'll look into the pilot jet tonight and see what I have in there but it should absolutely be between a 36-38? If not, change it correct? As for the air box design, well i won't go there catchers mitt is the first thing that comes to mind LOL. Thanks again for all your help trying to solve this problem, there are multiple (3-5) cases on the RYP forums i stumbled across last night with the same problem, most have never been resloved or just chalked up as "one of those things you learn to live with" So i do appreaciate all the time spent towards correcting this. Thanks, Adam Quote Link to comment Share on other sites More sharing options...
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