For my diff build i used black rtv before putting the diff together no leaks, i used a nice smooth layer of rtv ,and as for as my clutch bell end play very minimal play the engine im running is the Emx Wc picco 12 the gearing im running is16/60 21/55 tire size 58/60 CZ1 body, diffs 1,000,000 front 100,000 rear here in Florida the traction get pretty high, soon I will test a locked front diff will keep ya posted .

For my diff build i used black rtv before putting the diff together no leaks, i used a nice smooth layer of rtv ,and as for as my clutch bell end play very minimal play the engine im running is the Emx Wc picco 12 the gearing im running is16/60 21/55 tire size 58/60 CZ1 body, diffs 1,000,000 front 100,000 rear here in Florida the traction get pretty high, soon I will test a locked front diff will keep ya posted ,hopefully this helps.

I lightly sanded the diff housing also you will see the high a low spot sand till smooth and even

SickDuc,
To answer your question, I'm running an O.S. Speed T1204. Beautiful little motor. Been in love with O.S. Engines for forty years. Had to buy this little gem, as my old FF-320 Pegasus from a retired plane was overkill for 1/10 TC.

As far as my track, (and settings suited to a track), I'd like my baseline setup to be suited for easy driving on a blacktop parking lot. Unfortunately, there are no real on road racetracks in St. Louis, MO. When I say easy driving, I mainly mean I want the car to start moving (clutch engage) at a lower RPM, rather than having to wind it up before it even starts to roll away.

The modern clutch in this car is way more sophisticated than the clutches on all my old 1/8 scale cars: RC300, RC500 and Kyosho Vanning. Back then, installing the clutch on a K&B motor intended for an airplane usually required the use of a Dremel tool. And the only parts were the bell and two stamped metal shoes and a strip of material for the liner

I do love how Kyosho provides cross-section views of the clutch. That's helped me understand how it is supposed to work: the split (cut into three separate weights) clutch weights don't actually engage the bell at all, the centripetal force throws the weights outward (transversely), and by their angled face, they push axially away from the flywheel, and thus push the other weight (the one that is not cut into pieces) against the bell.

Considering track conditions, do the two different configurations of clutch weights (swing-style versus push-style) really behave that much differently?

Thanks all for the good information.

OK, watching Michael Slaven's video really, really helped me understand a few things.

The key takeaway for me is that there is a difference in the gap and "play". On page 34 of the manual, Step 60: "Step A" looks like that's the gap, and "Step B" is the play. As Salven demonstrates, he gets the gap set first (without bearings in), then adjusts for play after the bearings are installed. How I got so mixed up, was I was trying to shim and adjust all at once in one step.

I usually like to learn from reading rather than watching videos, but this time, watching Salven build his clutch really cleared things up for me.

Thanks for the useful information. I'm going to watch some of his other videos.

(Just catching up on all the replies to my posts; awesome information, and really fun to learn new stuff. Yah, Internet!)

The R4 manual to me is better than some others. But the pages on the clutch install could be more clear, proper dimensions on the cross sections, etc., rather than in the translated from Japanese side bar notes.

What helped me somewhat, and no joke here, was to open the PDF of the manual, and zoom in real close, and stare at it for a while with the parts on my desk. The sequence of installation, adjustments, and re-shimming, etc., could be better described along with proper dimensions and clear up some confusion. But sometimes the trial and error method and learning curve I'm climbing is a really good way to fully learn both the how and the why behind this. These things are too complicated to just blindly snap things together like a Lego set, and miss all the really important know-how of how the car really works.

Along those lines, I never bought my sons a RTR car--always a kit they have to assemble themselves. This way, they understand how it works, and WHEN something breaks or doesn't work, they know how to fix it--like a good mechanic.

I just got caught in the weeds with all the fancy modern workings of this clutch and 2-speed transmission.

Thanks all for the info!

So I just had a track day( high traction asphalt) and my clutch was set up swing style with the flywheel nut threading sticking out the clutch nut 0.6mm using the clutch spring supplied with 2 lines in it/1.8mm thick. That made the clutch engage just how you described you want yours ( we have the same engine). MS building the centax clutch isn’t much the same as kyosho’s but the idea is the same, have to get to the same outcome. As far as the gap, just add shims until it’s snug then remove the amount for desired gap( for example if you want .5mm and 1mm makes it snug/wont spin, remove .5mm of shims)..

I have used push style as well, the swing style felt more aggressive and maybe even too aggressive for very high grip..,IMO of course
As your clutch is now, when you are driving and you want the clutch to engage sooner, you can tighten the clutch nut spring through the little hole on the clutch bell. Line up the bell and notch in the nut and tighten about 1/8 of a turn, test drive and repeat if needed

SickDuc,

OK, that is a great post. You couldn't have been more clear with the how and the why. Very helpful. I just wish I could go out to my workshop today and play with the car. But I gotta pay rent. I'll play around with it this weekend and maybe report back. At this point, I know building and adjusting the clutch gap and play is no longer trial and error, and involves precise measurement and math for what shim to add or subtract. And adjusting the gap first, then the play in separate steps is the key. I think the manual tried to convey that, but not really.

For anyone else reading this post, go ahead and go to Kyosho's website, and order the shim pack for this car. I ordered two packs on impulse buy when placing an order for other stuff. But now that I know exactly how to do the math to determine exactly what shim to add or subtract, it's easy, especially since I have lots of spare shims. The kit leaves no spares (if you drop one of them). And when I first built this car, I only had an Imperial Units caliper. I bought a metric dial caliper, and that takes all the guesswork out of this. You can kind of feel with your fingertips which shim is which, but 0.5mm makes a big difference. Get a metric caliper if you don't already have one

Thanks again,
jcalchi

These clutch shims are just normal shims you can find on Amazon etc. Last I have bought bags of 100 pcs in several sizes.

Backup kit on the bottom also going to test bittydesign hyper 200

The RRR first gear spur fits perfectly, and the RRR belts are the same,so if anybody is running the r4 the RRR belts and the first spur gear im thinking the second gear may work also but may have to modify it some i will post pics of what I did to get second gear spur to work ,Im thinking with rrr spurs maybe little lighter im my opinion.

im using the blade bar from the RRR easier to setup with it 👌

Bittydesign

Also, worth noting that the top deck is 5mm lower than the Evo 2, and the diffs are smaller, plus the 2-speed shaft is lighter. This combo will definitely spool up quicker, kinda like the...

how do you set the front roll bar? I can’t get the sides to lift equally for the life of me.

it does spool quicker that for sure im running the Picco Emx wc 12 -16/60 21/55 .

Well ,the name i came up with is Kyosho V1RRR4EVo3 Bobby,s edtion lol I have brand new Shimo kit and brand r4evo3 kit will be taking r4evo3 drive train in putting it iall nto the Shimo edtion kit and we will see what happens