Cota 315 dimpled clutch plates

[Cube]

Hi there team,

I am looking to swap the clutch plates with new and dimpled ones to further reduce the drag. Now I have seen that some offers are different thicknesses and now I am curious. For example, one offer says "1.5mm thick. 0.1mm thicker than original ones.". I see the potential replacing the plates with "these thicker ones" and eliminate the gained less drag via the dimpled plates by putting thicker plates in.

So if you have swapped the original to dimpled plates or have knowledge about the original ones, can you please confirm:

• The thickness of the original plates (please also mention model year of your 315)
• Which dimpled plates did you use (manufacturer, model-no, thickness) and do they reduce the drag or not

I think this could be very useful for future queries reg this matter

Thanks,
Pascal

[slack]

Hello Cube, The best and cheapest mod i did on my 315 was to run Atf in gearbox eliminated the drag and transformed the clutch feel..

 

[Cube]

Hey mate,

thanks for your answer. I already switched to ATF and also removed two of the six springs from the clutch. Lastly mentioned made a much bigger difference. But I still have some drag left, too much in my opinion (which might be wrong). That's why I want to go ahead with the dimpled clutch plates. And I'd like to record it here for other people.....sooo many threads about this and none contain "the full story"

Hope this make sense.

Cheers,
Pascal

[larry s. k.]

Hi ,  I had clutch drag different brand model , , dissembled clutch scuffed disc and re ass ,  it still drag , a little  , engine  old 1972 ish ,  well  pulled clutch in , shift into first , raved up engine , could feel a little pull ,  clutch lever is still pulled ,, and it stoped the dragging , I did this with brake on , it might work for you ,noticed when bikes not used for periods of time clutch disc stick ,  and housing can be worn ,  a vr73 I have clutch disc froze , sitting for years , in frozen Shead , , engine  ran , but ,,, when clutch was attempted to use it broke the clutch drive ,, nut right off the shaft ,,  a Rickman montesa , I purchased , ,  a real barn find  now engine  is dissembled , haven’t got back to it yet , fix another , bultaco ,Cheers 

[b40rt]

On 3/24/2022 at 1:00 AM, Cube said:

Hi there team,

I am looking to swap the clutch plates with new and dimpled ones to further reduce the drag. Now I have seen that some offers are different thicknesses and now I am curious. For example, one offer says "1.5mm thick. 0.1mm thicker than original ones.". I see the potential replacing the plates with "these thicker ones" and eliminate the gained less drag via the dimpled plates by putting thicker plates in.

So if you have swapped the original to dimpled plates or have knowledge about the original ones, can you please confirm:

• The thickness of the original plates (please also mention model year of your 315)
• Which dimpled plates did you use (manufacturer, model-no, thickness) and do they reduce the drag or not

I think this could be very useful for future queries reg this matter

Thanks,
Pascal

I'm curious how reducing the clearance, by putting thicker plates in, can help reduce drag ?

[Cube]

37 minutes ago, b40rt said:

I'm curious how reducing the clearance, by putting thicker plates in, can help reduce drag ?

Well that's not really what i've said. 

Quote

I see the potential replacing the plates with "these thicker ones" and eliminate the gained less drag via the dimpled plates by putting thicker plates in.

The drag would be reduced by swapping to dimpled ones. But these new dimpled ones are thicker than the original ones(at least this is what they say), which would increase the drag again...so I wouldn't gain anything. That's why I try to find out about the thickness of the original ones, before I am going to buy a set.

Sorry if I expressed myself not proper. English is not my first/second language....sometimes it is a but of a struggle.

[caravan_monster]

Been round the houses with extra super duper special oils, polishing the tabs and basket fingers, dimpled plates etc. Think I tried the Apico dimpled plates at one point and they were somewhat all over the place on thickness, whereas the oem honda ones are iirc three distinct thicknesses. The aftermarket ones came with more plates than required, suggesting they could be relabelled CR250 packs. My experience with the 315R clutch 'cures' were that they work temporarily then fade away. Normally that quickly that they aren't worth the time and expense.

The most successful compromise I've tried described here:

https://www.trialscentral.com/forums/topic/69963-315-clutch-fix/#comment-482783

This was a compromise because it works, but there is a fine line in setting the biting point at the lever. Too far out and it will slip very slightly, but this is only perceivable if you bang it wide open at 30mph in fifth. Too close to the bars and getting neutral with the engine running gets finnicky. Bike gets used maybe thirty times a year on the easy route or practising. Set it up and it's still going fine. Think it's on 10/40W diesel engine oil now. It's a 2000 year showa model, can't remember if there were different clutches over the model years?

Edited to add, I'm using the standard oem plates (obviously fewer of them).

 

 

Edited March 25, 2022 by caravan_monster

[mcman56]

9 hours ago, caravan_monster said:

Been round the houses with extra super duper special oils, polishing the tabs and basket fingers, dimpled plates etc. Think I tried the Apico dimpled plates at one point and they were somewhat all over the place on thickness, whereas the oem honda ones are iirc three distinct thicknesses. The aftermarket ones came with more plates than required, suggesting they could be relabelled CR250 packs. My experience with the 315R clutch 'cures' were that they work temporarily then fade away. Normally that quickly that they aren't worth the time and expense.

The most successful compromise I've tried described here:

https://www.trialscentral.com/forums/topic/69963-315-clutch-fix/#comment-482783

This was a compromise because it works, but there is a fine line in setting the biting point at the lever. Too far out and it will slip very slightly, but this is only perceivable if you bang it wide open at 30mph in fifth. Too close to the bars and getting neutral with the engine running gets finnicky. Bike gets used maybe thirty times a year on the easy route or practising. Set it up and it's still going fine. Think it's on 10/40W diesel engine oil now. It's a 2000 year showa model, can't remember if there were different clutches over the model years?

Edited to add, I'm using the standard oem plates (obviously fewer of them).

 

 

Very interesting modification.  Over the years, I have heard of removing springs, spacing out spring mounting bolts and using thinner plates as a way to reduce drag but I fail to see the logic.  I can see that all of those things reduce the amount of spring force on the clutch and can make it easier to pull in.  However, as stated, isn't it the gap that allows the plates to separate.  Hydraulic fluid can be considered incompressible or nearly so so why would spring force affect drag with clutch in?  Is the theory that the outer clutch cover held by the springs flexes and will flex less with less spring force so there will be more gap?  Or maybe that the clutch line expands and will expand less with less spring force?  Has anyone tried to measure this?

[retromlc]

I sorted the clutch by doing the beta clutch fix and the ATF dextrose 3..., It was completely different I also took 2 springs out. 

[Cube]

21 minutes ago, retromlc said:

I sorted the clutch by doing the beta clutch fix and the ATF dextrose 3..., It was completely different I also took 2 springs out. 

What is the beta clutch fix?

[b40rt]

9 minutes ago, Cube said:

What is the beta clutch fix?

 

[Tristan]

Hi, ive just bought a 2004 315 to start with trials and it had bad clutch drag to the point it would constantly stall and be impossible to find neutral ect ect.

I renewed the master and slave cylinder o rings, bled countless times, tried various oils/atf, nothing cured it.

When I bought the bike it had the oem paper/Cork friction plates and aftermarket dimpled steel plates (1.5mm thick, 0.1mm thicker than oem steels) I presumed this was done my the previous owner to try and cure the drag without success.

The issue was really starting to annoy me by this point.

Next I contacted H&D racing and the guy offered me lots of advise, he advised me to use oem Honda smooth steel plates (1.4mm thick) with H&D aftermarket friction plates and the reccomended elf htx740 oil. 

I recieved these parts and fitted them to my bike, I wasn't holding by breath on it being cured by this point. 

I fired the bike into life, let it tick over for a minute or two, selected 1st and was pleased to find there was no drag whatsoever. I just hope it stay drag free.

So if your having issues with clutch drag then I would reccomend the oem Honda steel plates, H&D racing friction plates and the correct elf oil.

Edited March 31, 2022 by Tristan