Hey MACII, nice truck. I'm glad to see someone with enough balls to take on the nitroheads up at Wolcott. I just bought an SP1 and I hate it. Its such a beeznotch to get it tuned right (and DAMN those things are MESSY). I'm thinking about converting it to brushless. Thats why I went on this site to try to figure out what motor/esc/pinion combo to go with. Since its electric I think I might try it out on the indoor track.:018: I hope someone starts making a rtr lectric 8th scale so we can run a class. I like the stability of 1/8 but I can't stand the mess!

I "think" the problem with the metal pinion to metal spur is caused by friction and heat transfer. When the teeth engage and disengage eachother they drag and heat up. A plastic spur doesn't have this problem because the plastic is slippery. ALSO, plastic is a non coducter so the heat can not transfer from the motor to that gear.

Nitro engines can get away with metal to metal because there hp is LOW at low RPM. Thats why they have that crappy LAG when you hit the throttle! Lectric motors have max HP at 0 RPM! Thats why they kick arse!

ps. Lester is a really good driver. He beat me and Kevin by a lap last friday at the indoor track.:007:

But how do you adjust gear mesh with those holders? Are they mounted in slotted holes?

Sorry for the long delay since my last post. I've been having endless pinion troubles unfortunately with the E-CRT. No matter what pinion I try, it just eats them up. Even hardned pinions last two to three runs. It's getting very expensive to run the truck. Mike was a superstar as usual and sent me the Kyosho 46 spur with a 9 tooth pinion. That gearing is just about what I can use, still on the tall side but I should be able to finish races with it. My problem with that setup is just time, Madness is this weekend and the motor mount won't reach that gearing. I may try to dremmel it a bit but I know it's not my best skill.

(aside - the motor mount is adjustable because there are two slots drilled into the chassis. Mine were not done long enough nor were they countersunk so it could be lots better. I do however think this boat mounting system is NOT ideal, I'd rather have an "L" shape mount like one I saw months ago on RCCA's site. Unfortunately the guy making those stopped. Anyone out there who can? I'll bet there are lots of 1/8th conversion guys who would pay for that!)

(aside 2 - the 65 tooth plastic spur mentioned would be ideal in fact that is what I was using on my E-LSP. However it doesn't mount to the CRT Diff and {this is just like my luck} the diff it does mount to uses a 7mm hole. I'd need a 7x16 bearing which basically is not made (emailed Boca and a bunch of other bearing companies). I found some on eBay which are completely unshielded. Even still, I'm not 100% positive that the diff would be exactly the same width as the Jammin Diff...I'm investigating this to see if it can work. I've got the complete diff here and if I can't make the 46 kyosho setup work I'll try the eBay bearings.)

I missed the RC-Monster Bash this weekend mainly because two big race weekends back to back would likely cause a little discord to my marital bliss - but also because I was testing those Century Pinions this weekend. They seemed to go a big longer than some others but by 3 5-minute hard runs, they were done.

Other than this, the CRT has been going well. In my local club racing (at Xtreme RC in New Milford) I've been doing well. Generally I put a new pinion in and run Q1 and Q2, I sit out Q3 and put a new one on for the main. Fine Design has some clutch bell conversions which may work. I ordered two from him about 10 days ago but nothing has shown up yet. I hope they arrive before Madness if not, it's dremmel time!

Anyone going to Madness who is very good with a dremmel? I'll buy you lunch!

DM

If you want mac II. You can get the hot bodies diffs for the jammin. That would lower the diff ratio from 3.31 to a 4.3. The 65 tooth spur won't fit over the diff with out some modding. Just some suggestions.

Thanks, I had heard that changing ring and pinion would be an alternate fix for gearing. I'm saving that as a last resort...

@mac, did you tried the hardened pinions from towers? (the ones that are meant for the choppers)

You running a 9 46 now with the 3.31 diff. final 16.941
If you go with a 4.3 diff.
you can accually run a 11 46 gearing. 17.98
You could accually step up to a 12 tooth for more speed.
Not only that but it accually takes some pressure off the center diff.

Yep, those are the Century Pinions...they are better than most...3-4 runs before they are not useable.

DM

That's bad. I expected a bit more from them. Did you tried the hardened from Mike? i thought he had some nitro pinions fit a 5mm shaft..

They are some nice pinions to run on the plastic spurs. I got a few rene. I didn't know they was supposed to be hardened.

Tried those first...

http://www.visionarycomputer.net/rc/...iniondeath.jpg

Wow this pinion is destroyed...
The plastic spur is absolutely indispensable

No, i meant the hardened ones with the pressed on pinion. (the pinion of which was actually a clutchbell)

This one....

That is exactly what the one I pictured above looked like when it was new...hard to believe ehh?

Damn... i have the same problem with my Xray XB8TQ, the Kyosho plastic spur dont fit in this differential, and the metal spur eat my pinion very fastly :(

See if a Kyosho diff will fit the Xray... most cars use the same size bearings I believe, so it's just a matter fitting between the mounts.

holy cow..

I guess you are better of with using the standard pinion then. it will be harder.

Glass..
I try the diff Kyosho in Xray mount, but the diff is too long for the mount, the Xray diff is more little and shorter than Kyosho :(

That's bad Viruss. i know what you mean.. this is still a problem.. time to introduce the slipperential with a buggy mounting option!

I can mount on all the buggy?

Bump . . . . .

Any more news on this? I'm very interested in a successful Jammin CRT conversion. Please post any latest news if there is any.

Thanks.

Sure...lets see, I went to Monster Madness a bit unprepared. Still eating pinions every 3 runs or so...there I had a electonic meltdown...didn't realize it till after the event but I did band-aid it back together and TQ. Had a horrible main (my own fault) and finished 2nd behind Monster Mike... after that race I did some revamping. I bought an "L" shaped motor mount which is WAY better than the boat motor clamp. I swapped out the diffs for the LSP diffs in order to get a 25% reduction in gearing. I ditched the metal spur for one of the Kyosho 46 tooth spurs which Monster Mike sells here. Since all those changes I've run it several times and raced at the "Battery Blast" which was a decent race sponsored by RC Car Action at my local track, Xtreme RC in new Milford. I managed to take down the win at that one. I'm planning to run it again this weekend at the Lou's Half Fast Gas Blast which usually draws some interesting E-Vehicles (including usually Monster Mike's!)

I'm thinking of moving some components around for better weight balance next year, minor tweaks really. I have seen one which had the mechanical brake setup working and that is SUPER slick...I WISH I had brakes so I may try working that into the mix. My notes for anyone taking this on, ditch the steel spur ASAP. Also get a motor mount that is adjustable. Finally, try to incorporate mechanical brakes if possible.

Good luck.

DM

Nice. Thanks for the update! So how did that person run the manual brakes? That would be great.

It sounds like the change out to the LSP center diff and appropriate gearing was the big thing, eh? Any photos of your current setup?

Looks really GOOD!

I was a bit preoccupied so I didn't get a chance to see his setup. I'll likley see him at the Barn race this weekend so hopefully I can spy a bit more...I'll post some new pix of my the truck soon, it's a mess right now and will likely remain that way till after the race. Then it gets cleaned and I'll snap a few.

The LSP gears make it easier to gear, up and down...which really helps quite a bit.

DM

I don't think he changed the center. Just the front and rear.

Really? I thought his trouble was with the interface of the pinion and the center?

Did you change out the front and rear diffs?

He changed the front and rear to get the lower gear ratio. 4.3:1 instead of 3.31:1. He didn't change the center, only the spur...

Exactly as Squee mentioned. Front and rear Diff from an LSP and in the center I just popped the 46 tooth plastic spur on there. Without the change front and rear the gearing is WAY too tall to support the 46 tooth spur. You have to lower the ratio in order to use the smaller spur. (assuming the motor and batteries are the same)

Oh, I see. I was thinking for some reason that the center was how you changed the gear ratio. Cool. So was the 46T spur hard to get into the center assembly? Did you have to do much modification to it? I'm assuming the LSP front and rear diffs just dropped in to the Ofna diff housings?

Thanks for all the info by the way.

I run the 46T kyosho gear also, as well as a couple custom modded HPI Savage spur gears. They kyosho gears fit just like stock, only smaller.

I run a 1700kv motor so the gear ratio is not a problem with the 46T.

My CRT works great.. I got 2nd at my local trophy race... but I won't have it much longer though... it's going to a new home soon.

Any photos of that doc? As you probably have seen, the CRT is the vehicle I'm going to convert next and I would love to see more examples of conversions. So are you selling yours? Is it already sold?

Actually it's headed to Castle Creations to be used as a test platform for the Monster Max :D I'm within driving distance to CC and they want a truck to play with...

I think I have pics here somewhere.... hang on (searching fourms for "Jammin truggy"........................................... ........ )

Jammin thread with a couple pics... actually this is in the mock up stage with plastic motor mount etc but it shows the layout...

http://www.rc-monster.com/forum/show...=jammin+truggy

Cool Glass!!!

you are helping us out to get the monster maxx sooner!!

That's great man!!

I'm getting ready to convert my CRT to brushless and see there is a problem with pinion gears? I think your pinion problem is caused by chassis flex the nitro crt has a problem also the fix for the nitro motor is a 1 peice extended motor mount. Look into a brace to eliminate the flex in the center of the chassis by eliminating the battery box and brake servo and cutting down the top brace you have weakend the chassis. Grab the front and back of the truck and twist it and see if the pinion and spur mesh changes? :)

The problem is that the pinion takes all the abuse. Power isn't instant with nitro, but with brushless it is. That is the main problem. I can be cured by simply running a Kyosho plastic spur that Mike sells. It bolts right up to the stock center diff. Welcome to the forums by the way!

It's not flex. I've added a brace to couter that issue. It is as squee suggested. Nitro has a clutch, ours is just instant power. I've had good luck with the Kyosho spur but I'm still working a bug or two out. I destroyed two of them at a recent race, never done that before. I think it may be my motor mount...

It does not take much flex to eat a spur or pinion up though. Very little can
mean disaster.

My feeling is that for this thing to be totally bulletproof it needs a one piece mount for the motor which is attached to/the same as the diff mount. Having a two piece design is asking for trouble. I WISH I had the access to machines to build something like this but I can imagine a lower center diff mount- machined - which had a motor mount on the side of it. As it is now, I'm not 100% sure that I can get the motor and center diff on exactly the same horizontal plane. I'm confident that someone out there has the skills. Funny thing, with all the people converting 1/8th vehicles. I'll be whatever R&D someone invests in making a somewhat universal diff mount/motor mount will be repaid many times over by offering it for sale. Think about it.