questions for you 2 stroke guru's

i just aquired a shifter cart. Unsure of the year, but the engine is a YZ85 Yamaha. This cart ran great just before it was put into storage 3 years ago. All fluids were drained, and it was hung up in a vertical position. It was just taken down today and ive taken possession of it. The only problem im having (i havent gotten it cranked yet because of this), i cant get to clutch to disengage. Pull the lever in, it pulls the cable and the mechanism going into the motor, but with the cart in gear, you cannot turn the wheel without the motor turning.

I have NOT put oil into it yet as i dont have a clue about 2 strokes. I do know it requires pre-mix gas, but on the side of the motor it has an oil fill cap.

Am i missing something here?

 

Your tranny still requires oil, usually about 500ml.

The clutch is probably 'seized'. Quotation marks are to indicate that it's not that bad and just about normal after 3 years of dormancy...

The neanderthal way out, or the way I always do it is, start the engine in neutral, press brake, press clutch and shift in neutral. It usually does the trick.

If you're feeling anal or unsure, get the cover off and separate the metal & friction plates one by one.

HTH

 

thanks TZ. looks like the clutch is located on the BACKside of the motor, a royal pain in the ass to get to the cover without removing the engine. I believe i'll give your method a try. I just wish it had electric start, the only way to crank it is to push start it, or while its sitting on the stand, put it in gear and spin the rear wheel.

I guess i can just use regular motor oil in the motor?

 

There are transmission specific oils you can pick up at any MC shop...it would be better to run them than automotive oil in your YZ80. The clutch is tight behind the "yamaha" in the first pic.

 

Push start it then blip the motor with the clutch in and it will turn right loose normally.

I always run Rotella.

 

No disrespect to Mr Turner as I do not know his experience working on two strokes. I suggest you do not use any car engine oil in a 2T engine that has a 'wet' clutch. Go to your closest bike shop and buy transmission oil formulated for two stroke wet clutch engines. I use Maxima or Repsol but there are lots of good brands. While getting it to start by bumping it off is possible, you run the risk of doing damage if there is something amiss inside. Start by pulling the clutch cover off and disassembling the clutch (remove springs, pressure plate off, plates out) and inspect for damage or wear. I always replace plates as a set, either all steel plates, all fibre plates or both sets). If they aren't worn they may just need to be cleaned as they have probably sat in oil for too long and are "sticking". Brake cleaner spray works for this. Check the springs as two strokes tend to weaken the clutch springs. Put it all back togther and the clutch should work 'free'. While you are in there, check the clutch hub 'slots' for cupped wear. If extreme, the plates won't slide in and out properly causing a problem. You can lightly file any burrs if required.

Hope this helps.
parillaguy
(Honda RS250 racer)

 

Mr Turner actually has quite a bit of experience with 2-strokes. LOL I've heard mixed reactions from using Rotella or other automotive oils. Overall, any oil designed for a motorcycle engine will work in the crank case. They do make 2s specific oils, usually listed by "weight". I think 75w tends to be the lightest. I'd do what parillaguy suggested though. Open it up. The clutch isn't any different than what you have on your 4s. I'd assume you've replaced the clutch on that.

 

pulled the plates and cleaned them yesterday, worked like a charm. damn gasket tore on the bottom, so i have to order a new one of those, fuel tank is so old it had a couple of cracks in it, ordered a new one of those as well.

I put Motul 2 stroke oil in it (T800 or something like that). Damn stuff almost looks like blood.

 

I've been using synthetic Rotella for years in my RS125. Just saying...

 

Motul 800... most agree it's the best there is. Good choice. Castrol 747 seems to be a popular choice too.

For a small gasket tear I find that a dab of Honda or Yamabond liquid gasket does the trick till you can get a new one.

 

Todd with a tuner cart. Yeah, I don't see the possibility of trouble here at all.

 

I really didn't want to say anything, but this should be good...

 

I can definitely see the fun involved here...

 

Todd was this Toms? If so bring it over...OurI know where we can test her... The only thing I see missing is a good looking driver...Lord knows you wont be able to fufill that... Hey also I have a Extra one of these... ; )

 

gasket is on order.

yea Marc, its Tom's. :up:

 

Rotella

I hope you read this before you start your engine...

Motul 800 is a 2 stroke engine oil, you need Tranny Oil. If you used the blood red engine oil, you need to pull it out and replace it. They make Motul Transoil and Transoil Expert for 2 stroke transmission. Whoever sold you the 800T for your tranny should be shot.

Shell Rotella T is a diesel specific oil that doesn't have silicone modifiers in it so it works OK as an engine or transmission oil for motorcycles. I ran it for years in my SV650 and numerous others have put tens of thousands of miles on their bikes without issue. That said, the only other thing I have to add is that you should put all your steel clutch plates together and hold them on edge up to the light. If you see any gaps between the plates, they're warpped and need to be replaced.

Mr. Turner spent the better part of a decade tuning 2 strokes for his son to race (damn well I might add), his opinion should be considered.

PL

 

Todd, I got to spend some time in a 125 cart at CMP. Those things are very sweet. I've never been through a turn that fast before and they said I was still to slow.

 

im hoping to turn a few laps at Tally on it one of these days.

 

When you get to where you think your going way to fast, speed up. Then you will be getting close the driving it.

 

dude, just learning to shift the damn thing is gonna be a friggin challenge. steer/clutch/shift, all at the same time. Going into the corners fast, and trying to downshift is gonna be REALLY interesting.