bigboss

rmdhawaii

the car has been runing for a while
when i flip it upsite down it is flat, just alot of scratches on the bottom

and yes im on a set up board wen screwing in screws.

thanks

rmdhawaii

iTrader: (4)

The next thing I would try is:

Step 1: Assemble the car without the top deck, put on the brace and check if the chassis is bent.

Step 2: Screw down the top deck, putting the radio mount screws in last (show in red below) and checking (a) if the top deck and two radio mount holes align, (b) if the chassis is bent before you put in the two radio mount screws and (c) if the chassis is bent after putting in the two radio mount screws.

bigboss

step 1: without the top deck, the chassis is flat

step 2: i screwed in top deck with no radio mount screws, the chassis is flat.
(a) the top deck and radio mount seems to align.
(b) the chassis is only bent wen u put in 2 screws, 1 is fine

bigboss

please note that the chassis is only bent when i put in the body stiffener between the radio mount and the back, (part goes over the engine flywheel)

also i have notice, the chassis will wobble abit to the left with no engine, but with the engine the chassis will only wobble abit to the right

TomB

iTrader: (10)

i've had this beace and bent it into a "Z" shape. go with either stock or the kawahara carbonfibre brace if you want some bling and a psychological comfort

you might find that a bit of flex in the chassis is actually a good thing for low grip situations. i race on high traction so the kawahara cf brace is good. but consider your track conditions when upgrading. if you are stripping check the lower engine mount screws. i have found you need short ones closest to the left hand edge of the chassis and i use extra long ones on the inside two holes closest to the flywheel. use 222 loctite threadlock also, and a 2mm driver with no play.

rmdhawaii

iTrader: (4)

..

Bigbarn

iTrader: (13)

Sooooo............There must be an opening at Team Mugen......hmmmmmmmmmm.

Artificial-I

iTrader: (17)

Place your chassis on a piece of glass. If you press one end and it lifts up on another end , the chassis is bent/tweaked and needs replacement. Also dont press at the very end you might hit an edge and itll roll back and look like a bent chassis but in fact is flat.

rmdhawaii

iTrader: (4)

..

Artificial-I

iTrader: (17)

Yeah I just noticed that I was still back a page. Left this thread open all night. Either way best place to check a bent chassis is on glass as glass is very very flat.

Artificial-I

iTrader: (17)

Well guys. Here is your info!

How to rectify the 2nd gear spur stripping issue.
------------------------------------------

1. Adjust 2nd speed so the shifting is not so erradict or rapid. You want to tighten to two balls at top and bottom to give more space so the 2speed shoe is closer to the housing.

2. Dont run your tires too low. Go about 1mm bigger if your experiencing 2nd gear blow-outs. I believe what this does is keeps the rpms of the spur gear down and therefore will put less stress on it.

3. Changing from the aluminum to steel gear on the 2nd gear pinion. Part #t0736 , it has a duller edge and will not put as much stress on the spur gear.

4. Run the 18/24 Gear ratio on the pinion gears.

Mainly its believed to be perhaps a heat/friction issue. That if your car is in 2nd gear for awhile as well on a longer track that it will just heat up and melt.

On that note you might want to try an aftermarket spur (I will verify this myself). The low friction Delrin blue ones. This might help or worsen the issue so this is not a definent but its worth a try and I will get back to you guys on that. But wanted to throw it out there for others to test this.

This information was given to me from some friends @ mugen. I will try to get ahold of mike swauger as well and see his point on things and if they coincide with the issue and fixes.

But this information is surely different than what this thread has come up with so heres some new things to try guys.

Good luck. Happy Tuning. This info will be copied over to http://pro-hobby.net

-- A.I

kidDynomite

A.I., good to see you active on this thread.

And I know we all have covered and theorized the 2nd gear issue for a few hundred posts, but it's good to see it come up again, especially for the new guys that don't want to have to go back and lookup useful info. And if you're new, I would definitely recommend Rainer's (rmdhawaii) MTX-4 Knowledge Base site to get you up to speed. He put in a lot of work and data to give racers a place for reference and other news/info.

In addition to your notes: from my experience with stripped 2nd gear, it was a shifting issue. Closing up the gap helps prevent stripping bigtime.

Also noticed that with the stock chassis, if I clipped corner dots and got airborn or clipped a board, the chassis flex pulls the spur and pinion apart and that's when the spur gets chewed away. I also noticed that there was a crack in the rear bulk head where one of the brace screws go in. I'm sure that had a major reason for the gears to pull apart even more. I now have the Kawahara 4mm and will test this season. But if you stock chassis is tweaked, it could be flexing more than needs be.

A.I. Regarding the blue spurs. Are you talking about the 3Racing spurs? I believe they are out of round and most guys had bad results using them.

ShrekNZ

I too belived in glass being flat having used it for getting sealing surfaces to meet and until recently was using a glass cutting board as a setup board - until I checked it, it was curved by 1.0mm in the middle - I've gone back to my old setup board.

Artificial-I

iTrader: (17)

Thats bad glass then. Its still probably the most accurate surface. But if you trust your setup board. Then thats good too. I just notice a setup board to be a tad bit squishy too so it can sometimes mask a slight bend.

Artificial-I

iTrader: (17)

Thanks for the heads up. Yeah I think 3racing were the only ones who had them. Shoot , well Ill still give them a try and see how they fair.

Also read rmd's nitrokb site , it was a good re-introduction to the issue. But I wanted to hear from mugen what they had come up with. Perhaps im wrong but it seems their suggestions vary quite a bit from what weve seen in this thread.

Also it sounds like the kawahara brace might be the best route as CF will flex some , but wont bend. And your right with a metal brace that will reduce flex which will probably lower its grip in low traction situations. Since Ive already bit the bullet Ill let you guys know as I run a tight low-traction track.

But looks like Ill be picking up the kawahara in the mean time. Sounds like the best of both worlds and more durable , lighter etc etc. So glad to see they have this.