rm85 too lean

[scrpe_gme_crzy]

So I had found out my 85 had been running too lean... And wasn't getting much gas; probably why it wasn't starting. Also found out I have a stock main jet 125. And Idk how the sizes go. Could someone tell me what size I should get for more gas ? And how I fix the running too lean problem

 

[jus_me]

Well you almost answered your own question. If running lean than it is most likely the main jet. <<< That is if the engine is leak free..!!!
You first need to do a leak down test on it and then make sure the float height is correct.. I am not sure what it is supposed to be set at on those but all in all the procedures for that are the same as any other 2 stroke. Make sure it is leak free, make sure carb is clean, clean and oiled air filter, float height set correctly etc.. Then do a plug chop. If running lean then start high and work your way down on the main jet.

If it is a completely stock bike,,,, assuming the carb is stock and factory jetting,, you may have an air leak somewhere that needs attn first before messing with the jetting..

First confirm what the mods are and then what the jetting is in the carb.. Then report back.

 

[scrpe_gme_crzy]

Well you almost answered your own question. If running lean than it is most likely the main jet. <<< That is if the engine is leak free..!!!
You first need to do a leak down test on it and then then make sure the float height is correct.. I am not sure what it is supposed to be set at on those but all in all the procedures for that are the same as any other 2 stroke. Make sure it is leak free, make sure carb is clean, clean and oiled air filter, float height set correctly etc.. Then do a plug chop. If running lean then start high and work your way down..

If it is a completely stock bike,,,, assuming the carb is stock and factory jetting,, you may have an air leak somewhere that needs attn first before messing with the jetting..

First confirm what the mods are and then what the jetting is in the carb.. Then report back.

The float height is correct. It is set on 16mm. I have cleaned the carb recently and got it as best as I could. Fresh air filter. Not sure what a plug chop is. Could you explain ? And yes the carb is stock. I have v force 3 reeds fmf full exhaust. Air box lid off. That's it about engine parts. The main jet is 125 And the pilot is 50 i believe. But I do know that is has a crank case seal leak. Could that make a difference ? Also leaks a super tiny bit from where the cases split?

 

[Larry's Shee]

The float height is correct. It is set on 16mm. I have cleaned the carb recently and got it as best as I could. Fresh air filter. Not sure what a plug chop is. Could you explain ? And yes the carb is stock. I have v force 3 reeds fmf full exhaust. Air box lid off. That's it about engine parts. The main jet is 125 And the pilot is 50 i believe. But I do know that is has a crank case seal leak. Could that make a difference ? Also leaks a super tiny bit from where the cases split?

Those are two clues right there. Tho you don't say if it is a crank seal or other that is leaking, more info? From the jet sizes I see you have a Kehien. Double check main size and that it is original stock sizing. If you are sure it's a stock pipe, I would suggest starting at least two sizes larger. How did you determine it is lean?

As two case split leak, make sure screws in that area are tight. Some engines have gaskets, some just use case sealer. If it's just trans fluid leaking you may be alright.

Here's where I'll get flamed I have applied 3bond/Yammabond to the outside and stopped minor leaks. Area has to be cleaned with brake cleaner, engine has to be in position so that oil is off that area, let sealer set for 24 hours. Either lay bike over or flip upside down. Remove tank, bla, bla, bla before.

http://www.blasterforum.com/threads/leak-down-test-video.57629/ How to build one in DIY forum on here.

 

[scrpe_gme_crzy]

Those are two clues right there. Tho you don't say if it is a crank seal or other that is leaking, more info? From the jet sizes I see you have a Kehien. Double check main size and that it is original stock sizing. If you are sure it's a stock pipe, I would suggest starting at least two sizes larger. How did you determine it is lean?

As two case split leak, make sure screws in that area are tight. Some engines have gaskets, some just use case sealer. If it's just trans fluid leaking you may be alright.

Here's where I'll get flamed I have applied 3bond/Yammabond to the outside and stopped minor leaks. Area has to be cleaned with brake cleaner, engine has to be in position so that oil is off that area, let sealer set for 24 hours. Either lay bike over or flip upside down. Remove tank, bla, bla, bla before.

http://www.blasterforum.com/threads/leak-down-test-video.57629/ How to build one in DIY forum on here.

it is leaking from the crank seal. Only when it runs. It have a fmf not stock. And yes it is keHeinAfter running I thought it was running rich because it would bog when it hit the throttle fast. So I bought a hotter plug but I took the one out and it was dry and kinda white like a lean plug. Here's where it's leaking

and at the bottom of the flywheel. So I believe its the crank seal. Correct me if I'm wrong

 

[Blaaster]

As Larry said, leak test the engine.

Ride no more until you have fixed the leak, and put the correct heat range plug back in!

I will not flame you Larry, as I have seen bonding agent fix leaks a few times, but the leak should be fixed properly as there is no guarantee as to the expertise of the person doing the band aid procedure!

 

[scrpe_gme_crzy]

can I use permatex high heat gasket maker to fix the leak between the split of the cases ? And when replacing the crank seal is there timing on the flywheel? That's what confuses me

 

[scrpe_gme_crzy]

As Larry said, leak test the engine.

Ride no more until you have fixed the leak, and put the correct heat range plug back in!

I will not flame you Larry, as I have seen bonding agent fix leaks a few times, but the leak should be fixed properly as there is no guarantee as to the expertise of the person doing the band aid procedure!

And what size jet should I get ????? Idk the sizes. Also could I lower the jet needle clip?

 

[MercMenace]

The cases will need to be split. i believe the rm85s use an actual gasket to seal the case halves. I don;t think yamabond will work to seal the leak.

 

[scrpe_gme_crzy]

The cases will need to be split. i believe the rm85s use an actual gasket to seal the case halves. I don;t think yamabond will work to seal the leak.

They do use an actual gasket but I just want a temporary fix . If possible. Also you can get the crank seal with a nail and screw , not the best way but it'll get it done

 

[MercMenace]

I use a drywall screw to pull out the old seal. If you try and apply a band-aid to the case halves. I'm afraid it is going to be VERY temporary.

 

[Blaaster]

If there is a gasket there it will be soaked in oil and I fear that nothing will seal it as no sealant will bond in the prescence of oil.