Lock up clutch weights used

[Allspeeds]

If you read my build thread you will see I’m having clutch issues so as a matter of interest I’ve weighed a few bolts and washers to understand more weight added to the lock up for further testing.

id be interested to hear what other people use or run weight wise on there application weather it be turbo or high powered aspirated set ups  just to give me more of a guide line to question further issues I may or may not have 

[Arttu]

On my turbo GSX, about 300hp, I have been using pretty light weights. Usually just a bolt and nut on each arm combined with stock clutch springs. This has been working fine for years, on the road and for dyno sessions. But just recently I started to get some slipping every now and then. As quick fix I tried adding another nut on each arm but this helped just little. So apparently I have something else wrong with the clutch now...

Based on my experince clutches on turbo engines are a bit like black magic. If everything is done right and in good condition it can hold pretty serious power without any too dramatic tricks. But even smallest details can screw up everything and then it will slip or drag or whatever no matter what you do, until you find the actual problem.

Edited November 3, 2019 by Arttu

[Gixer1460]

12 minutes ago, Arttu said:

On my turbo GSX, about 300hp, I have been using pretty light weights. Usually just a bolt and nut on each arm combined with stock clutch springs. This has been working fine for years, on the road and for dyno sessions. But just recently I started to get some slipping every now and then. As quick fix I tried adding another nut on each arm but this helped just little. So apparently I have something else wrong with the clutch now...

Based on my experince clutches on turbo engines are a bit like black magic. If everything is done right and in good condition it can hold pretty serious power without any too dramatic tricks. But even smallest details can screw up everything and then it will slip or drag or whatever no matter what you do, until you find the actual problem.

I concur with Arttu's experience - my big hp turbo uses nothing more than 4x 12mm SS cap heads and SS nylocs - total. I know the pressure plate hub is fairly good condition ie. barely marked, its low miles but the engine has never not had a turbo fitted. Std.Suzuki plates and cheap as chips mineral oil changed regular seems to work. The old Kawazuki didn't run any weights on the arms at all - guess I was lucky?

[Allspeeds]

This is helpful feed back thank you least I have more than once in example to go off 

[clivegto]

As has been said clutch has to be spot on. Clutch steels would be the first thing I would look at for bleuing warpage. I replaced all the fibers & steels this summer (only use Suzuki ones). Look at correct clutch hight stake, no notches in basket. 

[Duckndive]

As IAN,s just the same only 240 beans but never had an issue..use cheap as chips supermarket mineral oil...

but do have to service every 3rd run up the strip....”plates dryed out”...

 

[Gixer1460]

12 hours ago, Duckndive said:

but do have to service every 3rd run up the strip....”plates dried out”...

High maintenance Drama Queen LOL! I used to take dry plates out and put clean dry plates back into Kev's ProMod slider for consistency - no oil ever on those fibres, just brake cleaner LOL!

[Screwriverracing]

I agree with just bolt and locknut, when it's spinning it creates a lot of force, so I would definitely be looking else where.

I always shotblast the steels so it grips really well when locked up.

doesnt make much difference with heavier bolts if you haven't got anything to compress it against.

Cheers SRR

[Allspeeds]

 Replacing the B plate (thin one) and judder springs with a full plate (I know I should of done this when I built the motor) I’ve also got heavier diagram springs cuming but I’m gona change my steals for new also the frictions are all new Suzuki but the steels were visually ok and within  service limit however service limit is for 98hp not 300 plus so il swap them out 

[Allspeeds]

The only other possibility is that because my turbo boosts hard from low revs the lock up isn’t getting Chance lock before the engine spools up hard ??

[Gixer1460]

Is this occurring on the dyno? It's a fairly abnormal operating condition ie. high load (tall gear) applied at a low rpm. If the dyno run was done 'all gear' you'd probably find it doesn't occur or to a lesser degree as the wheel speed is higher at lower load (gear) so the lock up tend to engage and apply pressure - just a theory?

[Allspeeds]

18 minutes ago, Gixer1460 said:

Is this occurring on the dyno? It's a fairly abnormal operating condition ie. high load (tall gear) applied at a low rpm. If the dyno run was done 'all gear' you'd probably find it doesn't occur or to a lesser degree as the wheel speed is higher at lower load (gear) so the lock up tend to engage and apply pressure - just a theory?

Yah I get ya mate we have considered doing next session in 5th and rolling on from a higher rpm for similar reasons you have just explained 

[Gixer1460]

Be wary with a run in 5th ! All dynojet dyno's have a speed limit of 200mph wheel speed hence why most use 4th - don't know about others but a half ton roller @ 10k rpm would pretty much go through anything if it got loose LOL!

[MeanBean49]

47 minutes ago, Allspeeds said:

Yah I get ya mate we have considered doing next session in 5th and rolling on from a higher rpm for similar reasons you have just explained 

No reason it shouldnt work from low rpm in high gears, high gear, lower rpm's is pretty much the only time in real world riding you get to actually use all the power and torque properly. If you cant do that whats the point? 

Sure its just a simple fix, they are pretty good when working

[Allspeeds]

Yah I’ve found 2 little improvements and one possible cause to do tomorrow on the assembly so hopefully she sorted then 

[Allspeeds]

33 minutes ago, Gixer1460 said:

Be wary with a run in 5th ! All dynojet dyno's have a speed limit of 200mph wheel speed hence why most use 4th - don't know about others but a half ton roller @ 10k rpm would pretty much go through anything if it got loose LOL!

[Duckndive]

12 hours ago, Gixer1460 said:

High maintenance Drama Queen LOL! I used to take dry plates out and put clean dry plates back into Kev's ProMod slider for consistency - no oil ever on those fibres, just brake cleaner LOL!

 Pot Kettle Black you did the clutch every pass

And know as well as me

Lock-up = wet plates  unless a pro stocker then dry plates ..

MTC Slider = Dry Plates  and clean every pass.... 

And my PRW slider lost the plot and went wrong way on set up.....but it was smooooth

[Allspeeds]

 Clutch all  back together with new steels and heavier springs feels a lot better on the lever in terms of strength fingers crossed we’re sort now 

Edited November 7, 2019 by Allspeeds