Brushless Truggy Part 2

[Shark413]

I am leaning towards the Tekno clutch. I mocked up the clutch and bell and it fit pretty good. I just need to move the motor mount back about 10mm and raise the diff to get a little more bell clearence. I can easily raise the diff by moving the spacers from the top to under the diff mounts. I will have to drill new holes to move the motor mount back.


I turned down a Traxxas flywheel to match the bell diameter.


If I raise the diff the cutout in the diff mount will match up with the bell and allow a little more clearence. I will also countersink the motor screws for more clearence as well.

[Shark413]

Here is the section that caused the damage. The arrow on the left is where you are supposed to land. The arrow on the right is where I landed.

[Shark413]

Ok after reading some of the other post on this site related to the Tekno clutch I decided to pull the trigger and I ordered one on Monday. It arrived today and I spent most of the night fabricating a new motor mount. I started by raising the center diff to give me more room, I then mounted the motor, attached the Tekno clutch (currently I am using MIP shoes) with a traxxas 15T bell. I also had to move the brake servo slightly to clear the bell. I hooked everything up and ran it on the bench just to see if it worked. The clutch acts just like a nitro clutch. When I gave it throttle the motor would spin but there was a slight lag before the bell would move, then as the speed picked up the motor spun the bell/spur at full power. This is just what I was looking for. Tomorrow I will put some street tires on and give it run in the yard to see how it performs under a load.


Here is the new motor mount next to a RC-Monster mount and my originally mount. The new mount has been extended to provide more support.


Here is the mount and Tekno clutch attached to the chassis.

[Shark413]

Update:

I was worried that the stock Revo 2 shoe clutch wouldn't be able to handle the weight of my truggy. So I ordered a special 3 shoe flywheel which arrived yesterday. So today I turned it down so it was even with the bell. This flywheel is the special NewEra flywheel made for the Revo. A little background, I have the Tekno adpater that allows you to use a standard Revo flywheel/bell, which uses two shoes and is smaller than a 1/8 scale bell. I wanted to use a heavy duty 3 shoe fullsized 1/8 scale flywheel/bell which is taller and normally wouldn't fit (too long front to back). The flywheel I got is specially made to be much thinner and allows a full size 1/8 bell in the same space as the stock Revo flywheel/bell.

I hooked it up with alloy shoes with no springs (so it engages sooner) and hooked it up. I took it for a spin and the clutch works great, it spools up smoothly before it engages, but once it engages it is very strong. Unfortunetly it was a little too strong and the combination of sticky tires, super powerful motor, wornout diffs and 100% traction blew out the rear diff. The diffs on this project have a lot of milage on them and were in need of a rebuild anyway. I spent the remander of the afternoon rebuilding both diffs. I hooked everything back up and ran it on workbench and it seemed to be working perfectly (too dark to run on the street). Off to the track tomorrow to see how it performs.


NewEra flywheel and full size 3 shoe 1/8 scale Ofna bell.


Stock Revo 2 shoe flywheel/bell.

[lincpimp]

That is nifty, any chance of a link to the flywheel? I like the idea, as I had wanted to use a clutch setup in my 2 speed yusa, and modded a 4tec 2 speed bell to work. The newera flywheel sounds like a much better idea.

Is this it? http://www.neweramodels.com/item.cgi...=&part_id=2643

Originally Posted by Shark413

Here is the section that caused the damage. The arrow on the left is where you are supposed to land. The arrow on the right is where I landed.

Looks like Hot Rod Hobbies? Haven't been there in a long time. What days do you usually go?

[Shark413]

lincpimp, yeah thats the flywheel I am using. Like I said I had to turn it down even with the bell so it would clear the brakes/diff mount. The portion of the flywheel that is normally used to start a nitro engine using a starter box is not needed and gets in the way when used in a brushless setup. I have a small lathe so I chucked it in there and just shaved off what I didn't need. I guess you could do the same using a drill and a file.

bluonyx, yes that is Hot Rod Hobbies. I am normally out there on Sunday's practicing/tuning my setups, with an occassional race squeezed in on Saturday. I was out there this past Sunday and Jimmy B. was having an on-road event so some of the expert nitro guys were there helping him out. Afterwards they came over to the dirt track and were driving their nitro buggies and they noticed me out there with my brushless buggy clearing the entire section in the picture above. They couldn't believe the brushless power/accelleration my buggy had and actually stopped to watch.

[Shark413]

Update: Took the truggy out this weekend for some testing. The clutch worked great and really did smooth out the brutal brushless power delivery. It felt almost nitro like with a lot more snap, but it was kind of weird because there was no nitro noise. Unfortunetly about half way thru the day I again stripped the plastic spur after landing hard. Apparently the clutch does not offer as much slip in this situation as I had hoped. I had a back-up diff with a steel spur that I mounted in the truck. I ran the rest of the day with no futher issues. Wear on the steel gears was minimal at the end of the day. I am still concerned with the stress on the drivetrain (enough to rip 4 teeth off the spur) so I would have liked a little more give with the clutch system (guess I have to wait for the slipperential). I did like the way the clutch smooths out the power delivery. So I now I need to decide if I should run the clutch or go with a hardened pinion and eliminate some of the complexity/maintenance that comes with using the clutch setup. I think I will run it as is for a litte while longer then decide.

[brushlessboy16]

did u try puting heavier springs in the clutch?