I picked up an ultra clrean mid-80's 350 recently. It was a one-owner bike with 75 total miles on it. It has the original tires on it.

I'm pretty experienced on bikes, running enduro and off-road stuff but trials is all new to me. I understand this about the bike:

bulletproof

needs modern brakes

20 lbs heavier than modern units

has a crappy carb and a 27mm swap is the ticket (Mikuni or Keihin?)

too heavy of flywheel and the 250 flywheel is the fix

stock fork springs are too soft for most

Beyond that, I'm clueless. I have a shop manual on order and am running down the exact year of the bike. Anything you can tell me would be greatly appreciated.

Thanks in advance

AP

Edited May 29, 200521 yr by AP_

If the rear shock has a remote nitrogen/oil bottle then it`s an 86. If not it will be a 1985.

If the rear shock has a remote nitrogen/oil bottle then it`s an 86. If not it will be a 1985.

Must be an '85 as I see no reservoir.

Are these shocks rebuildable?

More questions:

Are fork/shock springs readily had? These are way too soft - I'm right at 200lbs.

What carb is the set-up for a swap?

What tire pressure to run?

Any advantage to the '86 shock?

If the bike is well used then it would probably be cheaper to opt for a new shock, rather than try to get the original rebuilt. If you contact Bob Ginder at B&J Racing he will be able to help with all you are looking for suspension wise.

As to carbs the best replacement would be a PWK28 Keihin, which would make the bike run better, and provide a little more top end power. These are very good carbs, and do really make a difference if fitted to any bike which had a round slide carb originally.

PWK 28 it is. I put a PWK 39.5 on another bike and am very happy with the carb.

Suspension-wise this thing is way soft. I do my suspension on my 500 so a rebuild is pretty easy for me. I was wondering if there is a noticeable difference with the '86 shock with the reservoir or just freshen up what I have?

Thanks for the direction.

Edited May 30, 200521 yr by AP_

My favorite TY350 mods:

'86 shock with reservoir

Boyesen reed valve (and "stuffer') from '89 CR125

Footpegs moved down and back about an inch in each direction

Shave off about half of the band that is pressed on the flywheel for extra weight.

I never found the need for a new carb.

Blast and paint the inside of the rims (rustoleum rusty metal primer holds on like a rabid dog) as they tend to rust from the inside out.

Take care not to over-tighten the spokes. They are getting scarce and expensive.

Lengthen clutch throwout arm 3/4" and replace inner cable with something thinner and more flexible, and you'll have a 1-finger clutch that is almost as easy as a hydraulic.

There are probably more, but it's been a while.

If you're interested, I'll try to find my notes.

Oh yeah...I think I just added a little preload and a little heavier oil (10wt, maybe) and the fork was fine.

I have about 200lbs that I admit to.

AP, Did you buy the bike locally? If so, check with Mike at Hard Rock Trials. There's a good chance many of the mods mentioned in the previous posts have been done. Most of the TY350's in AZ that I've come across have been worked on. See you on AZTT for local trials news.

AP, Did you buy the bike locally?  If so, check with Mike at Hard Rock Trials.  There's a good chance many of the mods mentioned in the previous posts have been done.  Most of the TY350's in AZ that I've come across have been worked on.  See you on AZTT for local trials news.

It's painfully stock, 75 original miles.

Soft suspension is not necessarily bad for trials, you might hold off on that unless you're consistantly bottoming out. The flywheel and clutch mods are pretty standard. There are several TY350's around CAT, and the guys do pretty good in the morning classes. Mike at Hard Rock has lots of experience with the TY's. If you can't get the help you need locally, B&J Racing are very helpful and good folks to deal with.

Soft suspension is not necessarily bad for trials, you might hold off on that unless you're consistantly bottoming out.  The flywheel and clutch mods are pretty standard.  There are several TY350's around CAT, and the guys do pretty good in the morning classes. Mike at Hard Rock has lots of experience with the TY's.  If you can't get the help you need locally, B&J Racing are very helpful and good folks to deal with.

The clutch pull doesn't botther me, coming off a 500. I put some pvc spacers in the forks and they feel pretty nice but the shock is bottoming although it's on the hardest preload setting.

The fork springs can be modified for a stiffer rating. There is a tightly wound spring section at the top and a more loosely wound section at the bottom (tight means more coils per inch). The tight section is about 3 or 4 inches long and can be cut off. Heat and bend the newly exposed end to make the spring semi-flat on top and reinstall with new spacers with 3/16" preload. This mod was recommended to me and I found that it made a big difference. The bike handled much better and the forks did not bottom on every tiny jump on the loop. (No....it did not coil bind.) I have also done a similar mod to a Reflex with good success. I did not cut the whole tight end off on the Reflex but it is still a bit to soft.