XRAY - Model racing cars

hi all,

i haven't run my T4 yet - i am just about to buy an ESC (hobbywing justock) and 21.5 turn motor (stock, non turbo).

when i made inquiry re gearing with local racer, he said i need to look to get a "...Spur gear around the 60-64T mark, & a pinion around the 33-36T mark..." to race at the local track, which is relatively small and technical.

i referred to the list of spur gears in the T4 manual, and there's nothing less than 78T for 48P, or 92T for 64P...why is that?? why does Xray not sell gears that go down to the 60-64T mark?? I'd prefer not to have to go to a non-xray brand part!!

I may be wrong but you may not be able to fit that size of gearing and be able to still mesh the gears.

is anyone else running a T4 with a 21.5 brushless motor?? what are you running gear wise?

Get RW offset spur gears for the T3/4 - work extremely well and in range of sizes in both 48 & 64 dp can be purchased here

I use them on my T4 to get the ratios I need in 17.5 blinkly

Can't help you on ratio as I have only run 21.5T with boost/turbo and it does depend so much on the motor you are using, different motors have different characteristics (rpm or torque) and require to be geared to suit.

i was running 72 spur 29 pinion and it was fast

at ews same spur 31 pinion

You will be able to run 64/36 But I suspect not 60/33. Someone fromXRAY will be able to tell you the minimum no. of teeth on a T4, probably +/- 1

Sorry if this is a bit late. You can run the 64p xray 92 or 96 spur and xray 50 pinion to achieve the ratio desired.

I'm running my T4 21.5 Blinky with a 3.39 FDR with RW racing 66T spur and RW racing 37T pinion 48DP. Motor is a reedy sonic 21.5 with 32 degrees timing and a 40mm fan for cooling behind the motor blowing forward on a RSD mount. Other guys in my class are running FDR's between 3.04 and 3.7.