501 front shafts & hexes
 

I was wondering if anyone else has encountered the same problems as I have for the last 2 meetings. 1st one is that a front wheel nut coming loose despite me running hot bodies serrated wheel nuts. Should the tension be checked before every run ?
Secondly, I am having one of the cvd pins coming out of the drive shaft every couple of runs even though the grub screws were threadlocked in.
Any help would be much appreciated :thumbsup:

I found thread lock stopped my pins coming out, so not sure what else you can try to be honest.

With the front wheel nuts, again I thread lock them (I know they're already locking nuts) and then retighten between each run. Normally they have stayed fully tight with the thread lock though.

One warning on the latter, I find the thread lock makes the nut not always thread onto the axle properly, mine tend to strip about every 3 months and I change the wheel nuts at that point.

Ok thanks for that Dave, im assuming you mean the nuts strip and not the axles ??

Are you using a one way & are you losing the front right wheel?


Ive not had a problem with the cvd pins on the Tamiyas but if you've built them correctly and still can't stop it maybe you could try putting a tiny flat spot on the middle of the pin? That's what some of the HB D4 drivers have done as it seemed to be fairly common on that car.

yes and yes front right every time. What is it what is it ??????????

Ok well if its a flat spot thats needed then so be it

Front right because that is the side where the right-hand thread of the wheel nut is worked loose by the one-way rotation of the axles. On the other side it will tend to tighten.

Try using the newer Durga wheels from now on which are a snug fit and don't wobble on the hex at all, this should help to keep the wheel on.

It's hard to explain :bored:
The hex is moving slightly in the wheel - this movement is probably worse on some wheels - and certainly worse on more worn wheels.
Under power the front right wheel might rotate back slightly (relative to the axle) and because the HB nut is securely tightened to the wheel any movement of the wheel effects the nut.
So..... the nut loosens slightly - which allows the wheel maybe to move a little - which loosens the nut, which allows the whe..... well, you get the idea.
So from nowhere the wheel can spin off really quickly!
The left hand wheel will tighten up under acceleration, so that's no problem.


This is really evident on high grip and BAD wheels. That's not to say the original 501X wheels are BAD - but they aren't amazing. The new DB01 wheels look virtually identical but have a much tighter hex - and so far I've not had this problem.
Once your wheel has come off it will always come off with these nuts. They hold things so stongly but are only as good as the wheels they attach.

sosidge was so much neater in his explanation that he beat me to it, :thumbsup:

Ok thanks for the explanations. Weird though as the its always been on brand new wheels. 1st time out with new wheels today and it stripped the hex inside the wheel. I have also had it on 1 durga wheel but I dont think I was running the hb wheelnuts then. Looks like im gonna be running black wheels all the time now :(

I think they do white durga wheels too? I am going to try a set or two of them.

With my thread lock method, yeah its the nuts that go, but I end up changing the axles every so often too, after a while I can;t get the dried threadlock to come off the axle thread.

Its a not very elegant solution, but in the 1 and a bit year I've run the 501x, I had a wheel go very first meeting, and since then I've threadlocked and not lost one (though one came loose once), and gone through a couple of sets of wheelnuts and 2 sets of axles.

I was really paranoid about losing them, for about 3 months after the car came out you couldn't get spare hex's!!

ok lovely cheers Dave

Mate, the UJ issue, sounds daft but a lot of people did this when we were racing the Nats back in the 90's. Heat shrink over that bit of the Uj so then the pin wont come off, it sounds daft but does work.

Also have you tried Stu Wood, and asked him what issues he had? Worth a try anyway.

About CVD's pins, yes for sure you need to use thread lock, but you have lot of quality and hardness of thread lock !
Personally I use Loctite hard thread lock on the pressure screw thread but also on the end of the screw, like this I never loose a pin on 15 years of racing CVD's !
About wheel nut, the solution to be using US style nut !
The M4 thread looks pretty near than the US thread (CVD type)
Use aluminium Losi nut directly on original TRF wheel shaft !

For the fun, in Japan I saw satoshi Maeuzumi using Rayspeed rear hub, with B4 CVD's, when I ask why, he said that's just for big race to do not loose a wheel during the race, he use US type nut with MIP CVD's . Since he saw my car with my tip, he use evrytime ! :p

Dave, could you put some heatshrink around the cvd to help stop the pin popping out? When i ran my tam i used hot bodies wheel nuts and just kept checking them, did snap a wheel hex once mind:cry:

Hey looks exactly like what I said earlier, and it does work with the heatshrink (Brian Kinwald gave me the idea)

Right I have put some heat shrink over the cvd's which solves the issue of the pins coming although the nut is still coming loose :mad:
I tried some thread lock on the axle whilst still running the hb serrated nuts and it still came loose just before the end of my first run tonight :bored:
It just doesnt make too much sense to me as my first 2 meetings with the car went fine, surely the axles dont need replacing now after 5 meetings ?? :o
I will see if I can pick up some losi wheel nuts on sunday at worksop :cry: Can anyone help please ?

new wheels! The hex is sloppy and that's undoing these wheel nuts. If you want a wheel nut that won't come off easily (even with stripped wheels), use the kit ones but hammer them.. Woody showed me this 'tip' and yea, it really makes them tight. tight enough that I had a nightmare getting them off, but tight all the same :lol:

like I said, DB01 wheels should solve your problem as they are very tight on the hex.

Cheers Jimmy, I could really do without this ruining my day on sunday, I will go back to the standard ones whilst I try and get some losi ones. I have stripped 2 db01 wheels and about 3 501 wheels so far but the db01 wheels do feel much tighter. Im just suprised really at tamiya I guess :o

Dave, how about putting thread lock on the thread before you screw the wheel to the UJ. Then the other option is try other manufacturers wheel nuts. Im gonna try Kyosho, like what goes on the ZX5, as its slightly bigger and may be whats needed. I have noticed that the cars used at the worlds (Jimmys pics in the pic gallery) had different wheel nuts, slightly bigger so kindof gather that they had the same problem.

Have you tried putting a whasher on before the wheel nut? I know I had to do that with the front proto ujs that I was using on my Lazer.

Then there is the last option, and I can do a trial when I have the time. Drill two (as you have no hope in hell in allen keying the rears) wheel nuts thru the side and put in small pinion allen key screws (obviously threadlocked in) to the UJ. You may have to spend some time on the UJ and file a flat section on the thread end so you will always get a good slot for locking it to, but make sure you do it in the right spot otherwise youll have problems. I have done this before on my Lazer so it is doable.

You know me mate, if it doesnt work well first time when built then there is obviously a solution to make it work better.

Axial M4 wheel nuts have a good amount of nylon in them and secure the wheels quite well. Hopefully they will be back in stock soon so you guys can try some. The nylon does wear out and they do need to be replaced often (me especially because I remove the wheels and clean the tires nearly after each run at my local racetrack) but it's a small expense if you want the wheels to stay on! :)

http://www3.towerhobbies.com/cgi-bin...?&I=LXSAV0&P=7

Kyosho wheel nuts also work well and keep the wheels on better than Tamiya nuts also.

EDIT: Another fair price for 20 locknuts but I do not know how well these hold the wheels on.... someone else can try it :) http://www3.towerhobbies.com/cgi-bin...?&I=LXFUR5&P=7