SWM TL clutch upgrade

[Twinshockwobbler]

Hi all, new on here but have been looking at the thorny subject of SWM clutch upgrades on the TL models.

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/

[iconic558]

Much of the issues with these SWM clutches is simply down to incorrect clutch lever and perch, decent cable correctly routed, proper set up, roughed up steel plates once they get old and polished and draggy. 

Need to be OE Domino, but they get broken and owners go cheap, then the bikes change hands and, well you know. My mate had a brand new Tl320 back in the day and the clutch action was a revelation after Spainish ones. 

Out of all the twinshocks I've owned my TL320 had the lightest pull and smoothest consistent operation of all of them, Sherpas, Cotas, Honda TL, Ossa, even my Beta Rev I kid you not. 

 

[Twinshockwobbler]

Hi Iconic, yes your right about lever selection. Even Domino levers have their differences. I’ve just fitted a Domino lever blade with a pivot to nipple centre of 24mm and the difference in pull again is huge , the lever blade I took off it was 30mm. I suppose manufacturers bulk buy to a price so some bikes may have had these 30mm levers for that reason.Amal levers also do a 24mm pivot and their a nice lever but they need to be pulled almost back to the bars to clear all the drag. Other than maybe experimenting with different clutch springs, I don’t think I can improve on what I’ve now got other than finding a txr or climber outer case but if I’m honest I don’t think I’m that far off that level of lightnesses now, my son’s bike has the txr set up and it’s not much lighter

[jimg]

Wobbler, thanks for sharing.  I recently acquired a Jumbo (350) late model assembled in the USA.  Anyhow, the ball bearings on my bike are 12mm, so I got lucky.  Of course, my bike already has the clutch lightener arm and I'm using an "EZ-pull" lever.  Right now, it's a one finger pull, but I'm curious to using the smaller springs that you made reference to if it will make the pull lighter.  I just don't want the clutch to slip with the big 350 motor.  I'm in the process of installing new Rotax clutch plates (fiber and steel).  I believe I'm going to need to use 6 fibers, 5 steel, and 1 steel at 1.5mm (outer).  If your using stock top triple clamp, I'm using the "powermadd" handlebar riser that accepts fat bars... this makes a nice difference ergonomically, especially if you've lowered and went back with your footrests.  What length shock are you using on a Jumbo? Right now, my bike has 340mm length.  Regards.