Building a 1988 Suzuki RM250 engine

[rocket03]

I have some PJ1 7-32 Silverfire 2-Stroke Injector/Premix Oil. Would I still go that high (50:1) using this premix? I'd hate to lose the newly rebuilt motor by not running enough premix.

[Sandblaster]

I do not run that oil so I don't have first hand experience.
I went to their website but they do not specifically call out recommended mix ratios.

http://pj1.com/i-19004745-pj1-silverfir ... liter.html

I do have a bottle of the Gold series on the shelf.
This is what the back of the bottle shows..

20170727_170337.jpg (476.47 KiB) Viewed 7072 times

Take a look at the back of your bottle and see if it shows a recommendation.

[rocket03]

Mike, I decided to go with the Amsoil Dominator premix. If it works for you having the same bike then it's good enough for me. Thanks!

[Sandblaster]

No worries.
Get it jetted correctly and you won't have any issues.

[rocket03]

Mike, need your help on this. I have a brand new water pump impeller that was in the parts bin I bought. It looks like it may be too long, though. I have a shorter version that looks like it will fit once the case is fully lowered but I'd like to ask if you could recall what your impeller looked like and if it was a short or long stem. The guy I bought the parts from stated these were hard to find new and I was lucky he had one. The same guy who had four complete engine cases in the bin but didn't tell me one clutch case was for an RM125. The same one I decided to prep and paint to use on my rebuild!

https://scontent.fagc1-2.fna.fbcdn.net/ ... e=59ECF9E1

[Sandblaster]

It seemed to me it looked like this one..

rm250.png (173.13 KiB) Viewed 7038 times

[Sandblaster]

1988 rm250 impeller.jpg (123.55 KiB) Viewed 7037 times

[rocket03]

Mike, the water pump impeller you showed was not the correct one. It was actually the longer version I had.

Ok, now a major problem that I tried to not lay on you as I know I've picked your brain more than anyone on this rebuild. But, I'm stuck, really stuck!

I assembled the engine and got it back in the bike. I was attached the clutch cable to the case pin and found that the pin does not budge! I took the clutch cover back off and examined things but it all looks like it should! I thought maybe the rack pin was in wrong so I played around with that for a while but nothing helps! I even tried another clutch case from my parts bin but still, nothing!

The clutch basket that was in the motor when I disassembled I broke tabs off of. I had another similar basket in my parts bin plus bought a whole clutch setup off of eBay but neither works. The basket on the two I have is slightly different than the one that was in there. The one I broke had four solid tabs, two on each side where as the two I currently have have all tabs with the "U" shape in them.

I reassembled everything again today and was playing with the plates and could not get them to budge even with the cover off. It's almost like the springs are too tight or there are too many plates installed (I bought OEM Suzuki plates from Partzilla so it is correct). I followed all diagrams on assembly so it is together correct.

I am at a complete loss. I am thinking of springing for the Mitaka basket but would hate to fork out that kind of cash and still have things not work. The basket I'm using is in great shape with little to no marks where the plates sit. I have no idea! I was almost ready to take a sledge to the thing on Saturday!

https://www.facebook.com/photo.php?fbid ... =3&theater - image with what I have now.

https://www.facebook.com/photo.php?fbid ... =3&theater - image of original basket installed.

[Sandblaster]

This basket could be from 86-90ish...



This basket does not look like a RM250 basket from any year I am familiar with.



More research is required...
But, my guess is you have too many clutch plates or the clutch basket is thicker then stock...

[Sandblaster]

Did you use the correct clutch hub and pressure plate?
Or did you use the one from the odd basket?
And, you do have the correct amount of plates

Are there any numbers or letters on the basket?