I hate Tamiya three speeds

[A32Limited]

Yup, just like the title said, these things have to be the WORST transmission in radio control I've ever had the displeasure of dealing with. First, it was third having trouble, figured that problem out...there was a screw getting in the way of the linkage, since it likes to rotate around a bit.

Now, second has completely vanished, after putting it back together to try and figure out third...it worked up on the bench, but on the road, sorry, nothing. Though it DID engage a couple times for about half a second. It's done stupid things like this since I bought the truck. It sucks, and makes me want to drive it underneath a real semi...

EDIT: So now that I take it out of the truck...again. And pull it open...again, second magically works now. If all the teeth were gone, I'd be angry, but at least then it'd be something cool, but now it's just messing with me. I wonder just how much abuse a Tamiya semi can handle before it dies...Tempting.

[SonoranWraith]

Run the RC4WD R2. Freddy has done it in a couple builds. I think his daycab dumper didn't have room for the 3speed so he went with the R2.

[A32Limited]

I'm kinda leary on RC4WD's mechanical parts. I'm not very gentle on any of my vehicles, I like to run them to their limits, rather then build it to shelf it, and all of my friends that went with RC4WD driveline components are now running either TLT, or Axial. Lol

So after seeing that, $200 is steep to throw down on just a transmission. I love their tires though!

[FreddyGearDrive]

You might have a bent shift fork,or rod. OR someone put bearings in the slider,WHICH is a no no! Bushings are made to slide on the shaft,NOT bearings.
Could always go w/a r-2,I have quite a few trucks w/r-2s in them,& love them. But have a lot more w/tamiya 3 spds & never had a problem with one. If you can't find the problem,p/m me, & I'll see what I can do to help you out.
Good luck!
FGD

[A32Limited]

Checked all of those variables, everything seems to be in shape, and working good, so I guess I'll put it halfway back together, load it up and try it again, since it was sticky, or something...I wiggled the forks around, and it began working, so I oiled the shift linkage, and the slider where the contact plates slid on, hopefully that'll fix it, if not...I may just swap over to an Axial transmission with a 45 turn, and gear it up like my scaler, but I liked the novelty of shifting.

So far that's all it's been, is a novelty. LOL. Oh well, pick and choose, I guess.

[Tamiya Cowboy]

Wow over 25 3 speed trannys and I run them hard and I have never had them problems.

[A32Limited]

Well, drove the truck around for a good couple hours, did some full throttle starts, slamming the truck from gear to gear, and it worked everytime, so something was fouling it up, but I have no freaking clue what, which leaved me baffled, and mildly irritated. I know the servo is fine, but earlier, second gear was physically not there, period.

[ihbuilder]

when I had this prob on my 1st knew It was not mechanical this is when I learned of end point adj and centering on the radio . now I use the 3 position switch for shifting . If you lube that trans up when you put it together It should shift like a dozer sliding side ways on ice .



ihsteve

[A32Limited]

Originally Posted by ihbuilder

when I had this prob on my 1st knew It was not mechanical this is when I learned of end point adj and centering on the radio . now I use the 3 position switch for shifting . If you lube that trans up when you put it together It should shift like a dozer sliding side ways on ice .



ihsteve

Mine wasn't end points though, I have the linkage perfectly dialed in, I have the endpoints on my radio dialed to perfection as well, it shifted just fine, but second was completely gone...I guess it was just sticky or something.

My uncle's over too, he drives a truck for Roadway, I let him play with it, since he's dabbled a bit in RC stuff, and I dunno how, but he scrubbed the side walk with it LOL. Nothing major, scratched the bumper (I have two new ones standing by) And knocked my last remaining passenger side blinker off, luckily I was intending on getting new ones someday anyways, or making them. I just thought it was kinda funny...I'm relieved it was only the bumper that got scratched. Though I did run it into a bush myself, and damaged a couple little spots by the air vent on that side.

[CustomRCmodels]

I have to go here with the other guys ,
Tamiya 3 speeds are tough !
By all the crazy stuff I have done with mine over the years , I never had a busted one or issues with it !

But I did found over time several issues with these 3 speeds not being build correctly ,
( besides the deal with linkage , servos adjustments and such )
when I acquired used Tamiya semi’s .

Bend shift forks or worn bushing inside the shift-forks are a common issue for a not properly build or “high-mileage” 3 speed.
If you want to do an extra trick , you can bevel the tooth-flanks on each gear which is used for the shifting . Then you can shift this 3 speed even under load and with full throttle ( even thought not recommended way of driving ! )

It’s all a matter of how much care you take during the building process .
A few years back , during the first Indy show , I received this nice comment from several truckers :
“ how come all your trucks are driving so smooth ? “

Take your time building stuff and during the building process check things out .
If you get a ready to run vehicle build by somebody else ,
check it out real good , if the builders reputation is questionable , rip it apart and start from scratch ( that’s what I do when I buy used stuff )
Even with new stuff , just because it’s new , it doesn’t mean it’s right .

[oldboy]

I Have found that you can bypass the gear shift if you run MFUs'

Just lock the gearbox in which gear you want and the mfu will change speed in the different gear positions example,

in 1st on transmitter revs are low

in 2nd on transmitter revs are medium

in 3rd on transmitter revs are high

so now I am locking my gearboxes in second and lettin the mfu do the work
saves on servos and linkage adjustments also it stops the gearbox from neutralizing

so that removes the problem of lost gears

Oldboy

[TINY-TRUCKER]

I had the same probs with 1st gear would work, then 2 nd would work then 3rd would be just not there so then i just lock it in 1st or 2nd gear & leave it cause i would not be driving it to far so yer. it piss me off as well.

[ddc333]

http://www.stellamodels.net/catalog/...oducts_id=5071


might help gear changing ??

[SonoranWraith]

Originally Posted by ddc333

http://www.stellamodels.net/catalog/...oducts_id=5071


might help gear changing ??

Wow helical gears. Good thing they give you 3 pinions because tracking down replacement helical pinion would not be easy.

[ihbuilder]

I don't know about it helping gear changing since the gears do not slide .


IHSteve

[Juganought]

I wont even bother fitting second servo's to my rigs now. Gearbox is locked in first, fast enough for me

[sundance]

I have 28 trucks and never had a problem with the 3 speed.
take it apart and start over again.

[Lil Giants]

I have trucks with literally hundreds of miles on them in gruelling conditions and they shift perfectly till this day. I use the stock servos that come with the radio and have never changed a servo either.

I chuck that "servo saver" that comes with the trk kit and use the servo horn that comes with the servo, shortening it to what the servo saver device would be. I use the ball and plastic socket head on the servo and drill thru the plastic on the other end to screw the bolt into the locking collar on trans. That way the shift rod can't twist in opposite directions like with ball/sockets on both ends- messing with the necessary distance between shifts. That could be some of your trouble. Proper radio settings would be the other side of it.

[SonoranWraith]

Originally Posted by Lil Giants

I use the ball and plastic socket head on the servo and drill thru the plastic on the other end to screw the bolt into the locking collar on trans. That way the shift rod can't twist in opposite directions like with ball/sockets on both ends- messing with the necessary distance between shifts. That could be some of your trouble. Proper radio settings would be the other side of it.

Do you have a pic of this? I have considered doing this because mine seems to flop all over the place.

[Lil Giants]

I don't have a pic handy, I just drilled a 2.5mm hole thru center of plastic ball socket & screwed a regular philips head 3mm bolt thru it into locking collar. Set the distance between plastic sockets to the measurements shown in the manual and do your fine tuning between the gears within the radio.

You can see in this pic that I used something like a 20mm bolt thru the plastic socket into the lock collar on the trans to get the shift rod above the front powered axle, so even with the elevated shift rod the trans still shifted great.