TT250/Hawk aftermarket clutch parts?

[Megadan]

Honestly, I think the clutches in these bikes aren't assembled very well. Quite a few people have complained about the Hawks clutch being very inconsistent through the operating temp. range of the motors, myself included. There has been a couple of examples where people have gone as far as removing the stack, reinstalling and torqing everything, and it improved. So, that is evidence that things such as the pressure plate and its springs, or the plates and discs may not be installed properly;

Then there is also evidence that the oil itself is simply getting too hot, and as a result the clutch. JerryHawk in particular has said that after installing the oil cooler on his bike had stopped a majority of the before mentioned issues with the clutch adjustment as the bike gets hot, as well as a large decrease in color change in the motor oil from clutch material;

I plan on pulling the right side cover here soon to clean the oil spinner, and I am considering going a couple of steps further and digging into the clutch pack and pressure plate and re-seating everything just to see if it makes any sort of difference.

[Its_not_a_honda]

I will try taking it apart and reassembling.

I have had countless things start working after taking them apart. Just looking at it and putting it back together does wonders sometimes. lol

[Megadan]

Originally Posted by Its_not_a_honda

I will try taking it apart and reassembling.

I have had countless things start working after taking them apart. Just looking at it and putting it back together does wonders sometimes. lol

Hahaha, same here. My front brakes were iffy on my Hawk, then I started getting front pad chatter. Took the caliper apart, cleaned things, put it back together properly, and my brakes were twice as strong as before.

Just part of the reason these bikes are so cheap. It's just a lack of quality control on a fine scale. These bikes are pumped out by factories that get parts that were pumped out of another. Very basic quality checks and they are on their way. With a bit of care and attention on our end, we can make things work as they should.

Definitely report back what you find, or if you notice any improvement. I am curious.

[RogerWFarrier]

I had a Barnett in my Kz 1000 and it was complete garbage so I would stay away from those. After talking to guys they raced them I found that the hot setup was to use OEM frictions with springs that are 10-15% stiffer than stock. So if you could come up with a setup that is similar it should work well. I haven't seen any aftermarket parts though.

[Megadan]

Originally Posted by RogerWFarrier

I had a Barnett in my Kz 1000 and it was complete garbage so I would stay away from those. After talking to guys they raced them I found that the hot setup was to use OEM frictions with springs that are 10-15% stiffer than stock. So if you could come up with a setup that is similar it should work well. I haven't seen any aftermarket parts though.

I think some stiffer springs would be the ticket for my Hawk. The clutch pull is so light that a slight increase in lever effort wouldn't be an issue. If somebody had the specs for the clutch springs I doubt it would be hard to match up some aftermarket springs either. EBC has a whole range of pressure plate springs that are 10-15% stiffer than stock.

I have yet to get the gumption to take mine apart, so I have had no chance to do any measuring.

[Sullybiker]

Well, the replacement plates & springs from CSC have been sitting in my cupboard for a year. I learnt to live with it over the cooler months.

After the last oil change, and a commute in 80 degree weather, it was worse than ever. I guess the slightly thicker viscosity of the fresh oil might have aggravated it, but I can live it with no more. I stalled selecting first at an intersection and nearly got rear-ended, so I've checked the CSC manual for the procedure, put the fibre plates in a bath of new oil, and I'll attempt to change it out tomorrow.

If this doesn't improve things I'll look into the oil cooler solution that Jerryhawk mentioned. I do think that this is beyond the possibility of poor thermal management; it's only a 229cc motor, it's not getting that hot. I suspect poor assembly and/or some bad plates. Maybe the whole pack is thrown on the motor dry without any prep and it's a crapshoot whether it gets properly oiled at the factory with the first fill and test fire.

Put it this way, it can't possibly be worse.

[Megadan]

The oil is getting hotter than you think. It might not be outrageously hot, but it gets well beyond the thermal limit for viscosity stability, which is at least in part why the clutch behavior changes.

In any case, I hope the results are good! If you can, please measure the springs for me. it would be nice to find an option for stiffer/better quality clutch springs.

[Sullybiker]

Sure, I'll get measurements for you.

I'm not expecting the clutch to become smooth, I know the viscosity change causes that, it will likely always be a little snatchy when hot; I'd just like to stop the excessive drag, that'd be a win

[Megadan]

Just here to bug you and see if you managed to get those spring measurements?

Did you manage to get it back together and working? How is it doing?