S2R800 Dry Clutch Conversion

[RB]

GIF:
Cold start with the dry clutch conversion completed, I hesitate to say completed because I haven't taken it out for a shakedown ride yet. Once I have some flogging and heat cycles in her I'll be more confident. I used a KBike brand slipper clutch kit, not their conversion kit. On the 800cc wetclutch engines the drive shaft is shorter so I had a nut made by a friend machinist and milled the clutch drum down 6mm so I could get good engagement on the threaded driveshaft. There are a few minor variables I played with to get enough engagement on the big clutch nut and driveshaft.
1. Changed the shim behind the primary from 5mm to 4mm. Using 2x 2mm shims (McMaster-Carr is awesome)
2. Due to above I pushed the large clutch seal on the primary deeper so the clutch basket wouldn't rub.

There are two main concerns with my method of dry clutch conversion:
1. Choked the oil regulator on the main drive shaft where the push-rod resides
2. I used the wet clutch pushrod end as it had a longer collar and will hoepfully keep the needle bearing I inserted into the driveshaft seated for support.
3. Due to #2, I sunk and O ring into the shaft to help center the rod and keep the needle bearings from sliding more then necessary.
4. Longer pushrod is needed, but I used the end of another as a shim, much like some of the clutch slaves come with. THis gave me the proper length and utilized the wet clutch pushrod cap.

Some pics:


Operating table


Disassembly


Discovered wet clutch springs were shattered

[
Primary gears from 916/749


Didn't actually need to replace the oil pump (ProTIP, if you pull an oil pump refill through the oil pressure switch hole)


Black eye and busted face from the primary gear puller launching unexpectedly 6" off the bike!


removed primaries, notice I left the original wet clutch shim on the shaft, i want maximum oil splash on the bearings, another reason i used smaller OD shims.


2x 2mm shims to space the primaryinbord by 1mm


engagement moving the drive gear inboard 1mm


Mock up, you can see only about 2mm of threads, no gonna work


Making the nut, don't ask for a price, my friend made it on barter.


Clutch machine work, 6mm bore on the drum and 6mm extention  nut


dry fit



Powder coated old school clutch cover


second dry fit


All buttoned up, pay no attention to the extra long bolts, I have cut them down since

If I think of anything else I'll add it to this thread.

[Slide Panda]

Nice!

Still rocking that 800 from way back when I see.

[RB]

hahaha, yea way back in 2006

[koko64]

Great work

[stopintime]

Cool 

Where did the old truth go? The one that told us that the engine has to be split to do this? I kind of remember it had something to do with oil transport... block off/reroute?

[RB]

Well to be honest, to do a dry clutch conversion using only stock parts you do need to split the cases. This is only due to the length of the drive shaft. Now the second part of your question was oil transport and reroute or blocking. I found that on my 2006 803cc 2v, that there is an oil screw I which you can stop flow threw the drive shaft. This galley used to supply oil to the wet clutch so I just blocked it (read Install sheets for 848). I understand that the smaller CC engines were not equipped with the oil regulator screw and therefore no way to stop the flow of oil to the wet clutch.
Hope that makes sense

[RB]

Short shake down run and the clutch was slipping on heavy throttle. I never checked the clutch stack height, so instead of checking the height, I installed one more plate on the pressureplate side and it seems to have done the trick. So far no oil seeping or leaks on the push rod or splines. I'm gonna flog it Saturday and report back.

[ajw85]

This is amazing!

[koko64]

Again, great job looking forward to your ride report.

[Heath]

OK now I want my S2R800 back so I can do a dry clutch lol

[RB]

Ok guys got her out for a pretty decent shake down, about 40miles and all seems right and dry as planned haha. However, my downshifts are not landing like they used to and I've missed downshifts completely. When I miss a down shift I noticed I had to pull the clutch to its fullest travel and then I could shift down. This is only happening when I'm not at ideal engine load. As expected I can load the engine positive or negative to slip the gear in without pulling in the clutch lever, so thi problem I'm having is due to pushrod length. I made a new pushrod extension to hopefully solve this issue.

[savetheclutch]

this is freaking awesome!!! 

[ducpainter]

FWIW...I don't do clutchless downshifts with the slipper in my SBK.

[RB]

FWIW...I don't do clutchless downshifts with the slipper in my SBK.

I probably shouldn't have said 'clutchless', because I don't either. I should have said 'I slightly pull the clutch lever and the downshift slides in very smooth'. Thanks for pointing that out.
On a side note I just rode an S1000RR at the track, and it had clutchless shift, up and down, fulltime...silky smooth.

[koko64]

Nice.