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Stock spur gear no good??

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StevoRevo

StevoRevo

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Hey guys... i have... atm...a mainly stock 2.5 tmaxx that I've dropped a 3.3in... first time i tried to start it i stripped the 72tooth spur gear on the 2.5 transimission... went to my lhs... they only stock the stock spur... which is a 54tooth... got home.. pulled everything apart.... put the new spur on... and now i can't even get the clutch and spur to meet??? what the fu%*... PLease help!!!
 
Umm I think the spur gear you bought is for the newer T-MAXX 3.3. The newer ones use a smaller spur gear due to different gear ratios and no reverse. I have a T-MAXX 3.3 4908 which uses a 58t spur and a 22t clutchbell. The 54t is sold as an option part for the 4908 for those that want more top speed and less wheelies. Plus it has a different slipper clutch than the older 2.5.
 
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more help..??

Wish it was as simple as that ... but Nope, the spur gear i bought is the one for my model tmaxx 2.5.. the part number matches my instruction manual and everything... its just that even with the engine as close as it can go the spur and clutch dont meet???
 
Ok then try using a bigger clutchbell the 2.5 comes stock with a 19t bell try using a 20 or a 22t. Hope this helps. Or unhook the throttle arm from the carb and see if the engine will slide over a little more to meet spur then lengthen the throttle arm to compensate
 
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StevoRevo said:
Wish it was as simple as that ... but Nope, the spur gear i bought is the one for my model tmaxx 2.5.. the part number matches my instruction manual and everything... its just that even with the engine as close as it can go the spur and clutch dont meet???
Click to expand...

Then it's packaged wrong. The 3.3 spurs are in the 50 tooth range. 2.5's use a 72 stock. If you try to make up the difference with a huge clutch bell, your truck's gearing will be way too tall and the truck will not want to move. Stock gearing(20-72) is perfect for a 3.3 mated to a 2.5 tranny.
 
Wasn't this a used rig you rebuilt? If so the parts may not be what you thought they were.
Otherwise Matt has to be correct. None of these r/cs have enough adjustment to change spurs by 18 teeth.
 
thanks guys...

thanks guys.. turns out the dumb bit*# at my lhs can't read!! got some 72's on order now over the net... and my money back from the 2 dud spurs... precisely why i drive the extra 40 minutes to the next closest hobby shop... which is what i should of done in the first place... grrr... i just want to start my truck already!!!:angry:
 
You'll have your particular parts, especially the wear parts, memorized before you know it. Shopping gets funner as you learn more.:)
 
I originally had a 2.5 t-maxx not even close to stack anymore but still has the stock 2.5 trani and I ended up having to get a steel spur gear since all the torque behind the 3.3 stripped spur gears instantly. 4 spur gears later I decided to get a 72T Steel Spur gear and I havent had one problem with spur gears since. I also have an 18T clutch bell and put softer springs on the back so it doesn't flip itself over doing wheelies all the time. Oh I almost forgot that I also have aluminum parts on the front too and it still has enough power to wheelie haha.
 
Lhs

Pretty lucky on the LHS front.. i have three within an hour of my house... so I'm spoiled for choice... its just the phone calls and driving time and price comparing thats a pain... oh and the fact that when i got the right spur on (72t thanks guys!!!) and tried to start the break in on my new engine it turns out i must have put the tranny back togethor wrong cos it doesn't wanna move an inch forward but every time i start her she flies backwards whether its in reverse or drive!!! argh.... lol... oh well... my new spurs and clutchbell and ez start motor arrived today... n my new springs arrived yesterday... so it gives me a good reason to pull it all apart again anyway.... lol... kinda wouldnt mind just driving her a little bit though... :(
 
Just checkin cuz my buddy who's been in rc forever did the same thing with his he hit switch on remote to put it in reverse and somehow managed to crank his throttle trim all the way up without realizin it so when he started it it rocketed backwards dunno but figured id thro it out there
 

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