after pulling the clutch to bits several times and not being able to improve the standard set up i by chance got talking to Gary at Sportax Racing, he was able to supply the Aprilia type kit with 12mm ball bearings and also some standards generic to all motors, standards clutch springs. The springs are lighter than the 37mm ones fitted and also shorter at 33mm. The difference is massively noticeable ( just about one very strong finger😁). Apparently the 37mm springs are classed as heavy duty and due to their bulk when compressed, they can foul on the basket and posts. I also noted that on some of the friction plates, the material fouled the slots in the basket causing drag. This is easily cured with a bit of filing. The clutch is now drag free and far better to use, the 12mm ball kit also can be used on the 350 Jumbo and early fourstroke motors as well. Hope my first post on here is helpful. Oh and always use genuine Rotax crank seals,you really have to press them in compared to the push fit of some aftermarket ones👍 https://sportaxracing.co.uk/shop/clutch-kickstart/item-12-spring-239-625/

Haven't rode for 20 years, now live in S.Wales so thought I'd buy a bike to do some trail riding before I get too decrepit (I'm 68!) to ride. Used to ride a Ossa MAR, never in comps though.

Don't know much about the brand, apart from it's a pretty bike (shallow reason to buy, but you know!). The bike seems good for the price I paid.

It's a bit visually challenged, seat vinyl torn, frame paint missing etc., but seems to run well. Has been used in trials, so I think it's ok mechanically.

And some questions! Neutral seems hard to find when the engine is running, OK when engine stopped and slightly easier down from 2nd, rather then up from 1st? The decomp lever is broken off, still available or is there an alternative? Best oil for the gearbox, how much do I need and where is the drain and filler? And finally, fully, semi synthetic or mineral 2 stroke oil and what ratio? To be honest, don't know much about single cylinder 2 strokes.

Plan is to spend spring and summer using, then a restore/rebuild over next winter.

Thanks

Andy

Discovered five friction plates and six steel plates.  Should there be another friction plate? 

I am in the process of cleaning off the gaps in the plates, as I found some good material on this procedure elsewhere.  I've attached the pdf.

Appreciate any and all help.  Thanks!

Clutch_Fix-1.pdf

The previous owner had installed an electronic ignition that failed on him, so he reverted back to the stock point ignition. I reached out to the manufacturer (Rex’s Speed Shop in the UK), sent them the unit for testing, and, sure enough, the electronic ignition module was dead (which, according to them, never happens!!!). I got a replacement ($$), installed it, and got it all set up. The installation is pretty straightforward—you just need the right flywheel puller (which, of course, I didn’t have! 😒).

Next, I replaced the rear shocks. The bike had aftermarket Works Performance units that felt tired are no longer supported, so I swapped them out for a set of new shiny Falcon shocks (steel version), tuned to my weight.

I also installed HFS fork cartridges that I had ordered.  Installation pretty straightforward too.

Then came the carburetor. The only time I ran the bike, it was running horribly rich and leaking gas. So, the Dell’Orto PHBH 28 BS was due for a full rebuild and some new jets. But then I realized I had a spare Keihin PWK 28 lying around. Since all my other trials bikes use this carb, I am pretty familiar with it and I have a full set of jets for it. Would it fit? A quick check said YES 😋.

Off to the 3D printer I went, and a couple of hours later, I had a prototype mount—duct tape and all! I used the standard jetting I run in my modern trials bikes (280cc): a 125 main and a 48 pilot jet.

Took the bike out of the garage, put some gas in the tank, choke on... kick... The darn thing started 2nd  kick 🤩 and after warming up and a couple of adjustments on the air screw it ran like a champ! Yeah!

Next is finalizing the mounting and getting a trials appropriate needle (that particular carb was came off a MX bike and is running a MX needle).  And oh yeah... fix these horrible foot pegs! These have to be the worst even fitted on a trials bike.

I'll test ride it at the trials park tomorrow and see how much improved it is compared to the previous time I ran it.

Yeah, I know it's probably possible to make the bike run as well with the Dell'Orto than with the PWK, but in my experience (having done the swap on a couple of Gas Gas TXT Pro) the PWK is much easier to work with, get parts for, and tune.  But other people experience might be different.

Now, some people are going to say all these mods might not be permitted in Vintage trials competition (hydraulic clutch, D-slide carb in particular I think).  Well, here (West Coast USA) for the local club events I am going to run, the class I'll run is "twin shocks, air cooled, drum brakes".  Anything beyond that is permitted. 😁

Happy trails.

Engine oil

What engine oil do people use?  I my (modern) trials bike I use Maxima MTL 80WT.

How to verify oil level and refill? There are no oil level windows (unlike my Fantic) and I couldn't find an oil refill cap.  So I assume it's one of the screw on the clutch case.  Is that right?

Premix ratio

What is the recommendation for premix ratio when using modern pre-mix oils?  I have so many gas cans (from 32:1 to 130:1!) for various bikes / two strokes engines in my garage that I am hoping one will fall close enough!

Stock jetting

What's the stock jetting

Carb rebuild kit

Carb is leaking...  I did a thorough cleaning, needs a rebuild.  What's the recommended place to get genuine Dell Orto parts?

Suspensions

I am on the heavy side so I'll need stiffer springs (it just bottoms riding on the trails!).  What's the recommended rear shocks and where to find stiffer springs in the front?

Many more questions coming, so thank you all in advance for your help.

DC

  It took me a long time but last year I finally found a 80 SWM TL320. It's in rough shape needs a complete rebuild, I probably paid way too much and it's still not finished. When it's finished it will be my main trials bike for vintage trials. I would like to find another TL for back up also an Enduro GS SWM for vintage cross country. Where do you find these bikes? I look on Craigslist, eBay all the time. I never have even seen a SWM Enduro around here.

can anyone say if the bikes of this age had mineral oil @ the day and if it is still to recommend. The problem with neu oil types are that they seem to make trouble with seals. especialy the SWM has problems with oil leaks and needs new seals for the kicker and gear shaft at regular intervals.

A very helpful past owner of my 1982 tl 320 let me know how he set the clutch up. As follows:

• replaced clutch springs with 6 xr 650 valve springs A$35.00,
  
• whacked on a venhill clutch cable and
  
• uses a magura lever rather than standard
  

It works like a ty now, its great. I believe the plates were replaced with barnetts but still confirming that.

http://www.motoswm.co.uk/product-category/ignition/

 ) I replaced mine with I think one off an Aprilia TX/TXR/Climber which hit the footrest so with a bit of heat, well a lot of heat I bent it to match the original lever. I have dug it out from the dark corner of the garage to restore to a usable trials bike ( the joys of retirement)  but with the problem of being 20+ years older & having short legs I cannot get it to start !

I have purchased a new one off of Ebay apparently for an SWM but the only part that will fit is the spline Knuckle part the lever is still too short & will fowl the footrest. 

Pictures are of the one I bent with the one supplied which is 1/2" longer than mine & the Gori full length one & the bent one on my SWM so you can see how short it is.

Any help/ advice greatly appreciated, or has anyone successfully lengthened a kickstart?

Rich Hall