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need help with my rm 85 really smokey and boggy

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can anyone give me any advice on my rm85...

i have a carb its a KEIHIN PE28

the problem is i bought the bike with a vforce 3 reed block in it

i started it up and reved it and it seemed abit boggy on top end when i reved it . and thought it was alittle cold so didnt think anything of it ..

it as a standard exhaust with a dep tail pipe

the main jet standard is a 125

slow jet is a 50

jet needle is a 24naah

with the vforce 3 block do i have to lower the jet size or make it bigger??

i have tryed 122 129 and a 135 and the standard 125 and it dont make any differance . the bike is smoking alot even on over run .. you can rev it 1/4 throttle and it will start to splutter with smoke and if you just give it a quick rev the smoke is really bad. im running 40.1.. 5 ltrs could it be the crank seal as worn and burning some oil ... also on the carb its self where the main jet screws into . you have a long shaft which screws into the carb you have a lock nut can someone give me some idea on how to set this should i just screw it all the way in untill it reaches the lock nut ...

if anyone as a suzuki rm 85 and there using a vforce 3 block and you give me the jetting spec so i have some idea where to start

:thumbsup:

cheers

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I don't think it has anything to do with the Vforce...sounds like it is time for a rebuild. Tdub

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check out the power valve mechanism above the exhaust port, make sure all is well, i am currently dealing with that situation, it may be time for a top end?

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your jetting is jacked up. Is your plug all wet and sooty? adjust your pilot air screw first on the outside of the carb. Not the idle screw. Two separate screws. try screwing it in all the way and back it out 2 turns. get a manual and see what stock jetting is. needle clip position exc...with the rad valve spacer you will need to a size richer on the main if u put it on a stock bike. Forget that right now. When you take off in first gear, does it go bwwwwwwwwwwwwwwwwaaaa? Like it almost runs out of gas? If so go bigger on the pilot jet till you get a crisp throttle response. Bring the needle clip up one notch to drop the needle to lean it out a tad. Try going one plug hotter (lower number). Make sure your jets are cleared out and you can see through the little holes. With the lock nut where the main screws into you are talking about the needle jet itself and yes screw that in all the way. Then screw the main jet on that (if that is what you are talking about)

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hello renner

yes the plug is all wet and sooty. i have set the air screw turns out. what it says in the manual..when i took the carb off it had a 135 main jet in it which infact stock is 125.... the needle setting and the slow jet are what is says in the manual apart from the 135 main jet which i have put the standard 125 main jet back in so everything now is set to the stock.when you talk about rad valve spacer are you talking about the vforced3 block ???

when you take off in 1st gear as the bike revs harder it starts to splutter like it cant clear itsself .. as you change gear you dont seem to notice it because your not hitting the same rev range as you change gear. yes im talking about the needle jet itself you screw it in and then the main jet screws into that.. but this is the first time i have seen a needle jet with a lock nut on it .. is that for very fine tuning ??.. all the jets are clean float height is fine ..you get that bbbbbbwwwwwwwaaaa when you try to rev it up and lots of smoke ... im thinking it might be crank case seal so i have took it out and the new seal is on order ... will arrive tomorrow ...

cheers renner

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renner. i have also took the head and barrel off to check to see if the power valve was ok . the piston looks new no scratches or scores and barrel is the same all good there .. when i took the exhaust off there must of been 30 to 40 mm of oil in there which spilled out. i have washed it out now . and when i took the power valve cover off it also had some in there as well so cleaned it all out ..i put a small pipe in the bottom of the crank case and suck some fuel out not alot in there no oil like what came out of the exhaust...did that because i thought if the crank seal was ok it might of been the gasket but i think thats ok because no oil in crank case....i have taken the carb off again and everything in there looks standard.. i even screwed the needle jet all the way in and locked it off as you said.. needle is set on number 3 grove. im just hoping that it was the cranck seal which had let go.....

but saying that everything is standard on the bike apart from the tail pipe which is a dep ... so do you think with having that vforce3 reed block on standard book specs is making it run that rich

spuddy

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No with the vforce you should run a richer main. I don't know about going to a 135 from a 125. I would try dropping the needle go one notch up. Make sure your filter is clean and the silencer packing is not completely soaked in oil. I would just re-pack it if it is not rivited. Run 40:1 premix. So are you running a 125 main in now? Do a plug check at wide open throttle. Run it as fast as it goes on a long road, push in the clutch and kill button, coast to a stop and bust out the wrench in your pocket and take the plug out and look at it. Is it still sooty? Is it white? Golden brown? Tell me what you find. Dropping the needle (one notch up) should make it run crisper. If it is running rich.

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hi jenner

yes i have put the standard 125 back in it now . when i got the bike there was a 135 in it i dont want to run the bike on a 125 and drop the needle down that will make it even leaner.its funny how alot of people who race bikes use a vforce 3 reed block you would of thought that someone would of said to me . hey phil just go richer one size on the main jet...anyway going to put the biuke back together today i have another dep end can to put on so repacking will have to wait ....

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hi renner

seal asn't come yet so cant put bike back together .. anyway i rang hardcore racing up today and they are the main dealer import for the vforce3 blocks to the uk

anyway i chatted to the tec guy and he said that because my son isnt riding the bike hard 125 jet is fine and drop the slow jet from a 50 to a 42. 1 1/2 turns out on the air screw.. once he starts to ride the bike harder then drop the main jet to a 122..

does that sound right to you ????

will give it a go once i put the thing back together and order a 42 slow jet

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no leaning out the main once he gets good does not make sense to me. He is going to be on it more I would go up on the main. If you ride hard with a lean main, you will lock it up.

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no leaning out the main once he gets good does not make sense to me. He is going to be on it more I would go up on the main. If you ride hard with a lean main, you will lock it up.

Makes perfect sense... when he rides it harder he is pulling higher RPM which in turn will have a stronger intake signal, which in turn will draw more fuel thru the same size MJ. Same with putting a higher flowing pipe or intake on...going richer is not always required. Tdub

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didnt read ur stuff but my friend bought eli tomacs bike got it rebuilt and ported still bogged the reed valve was cracked thats all and it would go brapp bog bog bog now it hauls ass!!! we fixed it

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