Shimming diffs in FLM Hybrid Bulks
 

Is this necessary? and where do I get the shimms, can't find a HB # for them. I am guessing that they have a 8mm id and 10-12mm od?!

No shimming necessary then!

I will hold all of you accountable if my diffs strip out!

They require allmost no shimming, (i would like to have a little more room in them though) i think i only shimmed the pinion gear in mine.

I used Kyosho shimms, they come in 8mm ID, and .1, .2 and .3 mm thickness, and tamiya makes 10mm id shimms with the same thicknesses.

If you need cheap .5mm thick 6 or 7 id shimms, traxxas has these in teflon.

Thanks Serum.

I've been running mine without shims since the snow melted this spring and I checked them the other day. Absolutely no noticeable wear.

Am I correct that id means in drive and od means out drive? Because I need to shim my pinion. It has too much play and will slide in a hit the cup. These would be 8mm in drive, correct?

ID means inside of shim or circle
OD means outside of shim or circle

Thanks. Since my pinion is sliding in I need to shim the outside near the dogbone cup right?

Thats correct, if it is sliding in and out, the pinion shaft needs to be shimmed between the bearing and the drive cup, also make sure you can maintain the correct tolerance inside the diff after you shim it

Thanks for the help. They are 8mm shims right?

that im not to sure of

Would these be the shims to use with HB 1/8 diffs?http://www.shopkyosho.com/product/pa...er=96644/410.0
And when using Revo stub axles what size shims would I need for those?

Btw about how many shims come in a kit?

Im not really sure, as I will be getting my cases this week my self, but I think I will be able to use the shims I have in my UE diff cases to help me out , if need be....but those look like the right ones, I'll let someone else pipe-in, to confirm this

I got this reply from Rene:

"Yeah, that's an 8.

I got a set of kyosho shimms, 10 of each; .1 mm, .2 mm and .3mm.


I just PMed Rene. I think that is them but I am not sure.

I think those are it, they are the only
8mm on the site.

I bought 2 6 spyder diff kits from bnighs on UE forum. These are the same diffs as in the UE Ultralights (no cases) except the output shafts are stock 7.5. Ben supplied the correct UE diff output shafts, 8mm pinion drive cup and a set of shims as well. I finished shimming the front bulk last week - it took .022 total in shims on the carrier to zero the side to side play and .016 on the pinion (between the pinion and 1st bearing) to set mesh right. If you'll read UE's write up for shimming the Ultralights - its pretty much same kind of thing and all the pics help understand what needs to be done.

You take the freeplay out of the pinion by how you tighten the pinion drive cup. Take the hybrid side that will hold the ring gear face up and place the shimmed pinion with brgs in it. I took a knife blade and placed it between the cup and pinion and applied ever so little pressure to the pinion and then put the drive cup on and tightened the set screw while holdingthis pressure - this removes all the play and will not let the pinion hit the cup. If you just push the drive cup onto the pinion shaft, you'll wind up with play. The pinion should not move in and out when you're finished.

I ran into a prob with the rear hybrid - it would not hold the pinion brgs - it was made with too much clearance. But FLM stood behind it and my replacement should be mailed tomorrow so hopefully, I can finish the rear diff and install these and the cvds this week.

I don't know what the HB diffs need shim wise, but I'd be surprised if they needed no shimming.

The HB diffs do require shimming. Mine only needed the shims on the pinion, as the diff fit with no side to side play. I think I used 3 of these shims on each pinion:

http://www3.towerhobbies.com/cgi-bin...?&I=LXGPC9&P=7

Thanks everbody!! Got it!

Thanks I'll order a set.

Thanks for the link Linc :lol:

I was searching everywhere for these.

I got my Hybrids in the mail yesterday, and all I had to shim was the pinion, I had to put a shim between the inner bearing and the gear, and also one between the cup and outer bearing,

Mine only need pinion shims also. You "gotta luv it".

I guess its pretty obvious what diff FLM used when they designed their hybrids. At least I was able to use the Kyosho based 7.5 diffs which I already had.

I got a little problem. My case are too tight. The bind with no shims. I have tried putting the internals in the other case but the problem persists. Is it possible to grind the case so that the bearing will sit a little deeper? Is there a head for the Dremel that fit that bearing hole?

I had the very same problem with mine.

I took out the gasket between the diffcase and the ringgear and use loctite silicone gasket. (it gives you a good .5mm more clearance.)

Thanks Rene.

I'll try it that is about all I need.

Mark

Arrrgghh!!!!!!!!
 

I have been trying to get these thing shimmed for days! #@/!* I can't seem to get them. One works perfect. The other one though is a real pain.:diablo:

Renée, I tried your suggestion however now the pinion is binding. Does anyone have suggestions for me? Out of desperation last night I sent Mike an e-mail asking if he would put them together for me. Do I feel I like a noob.:oops:

Mark

This may sound dumb, but have you removed the bearing on the ring gear side and check to make sure some dirt, etc is not making it stand away from the ring gear? Or maybe swap the bearings side to side and see of that helps. If your ring and pinion are binding it means that something is pushing the diff over towards the pinion. Are you using hb diffs?

Yep, i am using Hb diffs with hybrid bulks. To remove the bearing, I have to open the case and slide out the pin underneath the gear corret?

Yeah, the cross pin holds the diff output in place. I an suprised that you are having problems, my hb diffs went in perfectly, but I did have to shim the pinion as it was not deep enough into the case and was not meshing completely with the ring gear. Are your diffs new or used, and are they the truggy or buggy diffs? I have buggy diffs in mine. The only difference is the ring gear, the cups, internals, etc. are the same. The only reason I ask is there must be something behind that bearing, or maybe the diff case is not machined correctly. Have you had a good look at the case where the bearing sits?

My pinion wasn't deep enough also and that was easy. They are new diffs, not the PRO diffs. I am not sure about buggy or truggy. They are the ones closest to the OE E-Maxx diffs. I don't have a way to machine out the case. The bearing does sit very tight. It is hard to get in and out of that half.

Check to see if there is no stuff in the bearing holes. use a toothpick to poke them out.

Are you using the 43/13 or the 43/10 diffs? if everything is tight in place, it's pretty hard to solve the problem. It either takes a deeper bearing hole behind the ringgear or behind the pinion.

The 43/13 diffs do fit in my diffs.

With no pinion in place; have you got any room on the diff inside the case? (4 screws tight in the diff, 3 screws tight in the bulks) try to see if you can move the diff left/right

The truggy diffs have spiral cut gears, the buggy diffs are 'normal'- easy way to tell the difference...

They are both spiral cut Neil.

My buggy gears were straight cut. Sounds like kruse has buggy diffs too, if he is trying to keep the ratio as close as possible to the stock emaxx ratio. If you are still having issues maybe I can meet up with you, I am only about 30mins north of you in Slidell. We can compare my diff case to yours, as I have to take mine apart again to put the modified output shafts in the diffs to run my ths cvd cups.

Huh? I thought the truggy diffs had spiraling teeth on the pinion & ring gear, like this:

http://www3.towerhobbies.com/cgi-bin...&I=LXJBM3&P=SM
http://www2.towerhobbies.com/cgi-bin...&I=LXJBM4&P=SM


and the buggy diffs have normal teeth, as it were:

http://www3.towerhobbies.com/cgi-bin...&I=LXLGU1&P=SM
http://www3.towerhobbies.com/cgi-bin...&I=LXLGT9&P=SM

EDIT: Images dont work, but links to parts do.
EDIT: I type too slow...

Thanks for trying to help guys. These are the diffs:

http://www.rc-monster.com/proddetail...HPI_BUGGY_DIFF

One set fits perfect. The other I cannot close the case. I will check again(after work) to make sure it is clean maybe I missed something.

Since this case is the only one that all 4 bearings sit very tight in, it is logical to assume that the problem is the bearing seat in this case. Do you think Mike or FLM could change it out or machine out another .5mm?

Sure, don't worry about it. If the housing is wrong, FLM will fix it for sure!

God bless The Monster and his army of elves.:angel: I just an E-Mail from Mike that he would fix it!!!!!!!!!:yipi:

Thanks again guys. I'l check this afternoon for dirt if none I'll send everything to Mike.:mdr:

Duster 360 is right about how to tighten the pinion, his methed for taking the slop out is exactly what I do the pinion can't move in and out anymore it also takes the side to side slop out of the pinion as well. Just remember not to put to much pressure on the pinion and drive cup when you tighten it or it will start to bind the bearings a little. If you don't use a good threadlocker on the set screw it will come loose and you will have to take everything apart again and do it over.