i did see the hex is narrower but i didn't measure the stock width to the new hex hubs for width

Thanks.

If I get one that's a lot faster will it be easy to tell how far to turn it down - to 10.5 - 13.5 - 17.5 or will that be a lot of changing gears and trying to match someone with that speed motor?

What I meant was to buy an 8.5, gear it as an 8.5 but turn your current limiter way up (meaning down for less current) on your esc, your punch setting(s) way down on your ESC and set your throttle epa to something like 85-90% on your radio. You'll have a very cool running 8.5 at that point that will be very similar in speed to a 10.5. Since I assumed by your original question that you were going to buy a 10.5 to run in an open mod class, how far to turn it down will be answered by how well you control it rather than trying to match any other specific motors' speed but it is quite easy to dial-down a mod motor, it just takes a mentality few racers have. :)

Thanks Mark! Very helpful.
I actually do want the fastest motor I can get and still be able to tune it down for when I do race. I'm still pretty new and haven't raced much yet - only a couple days of heats on-road touring back in december.

I just got an SC10RS today and I'm wondering if there are any parts that break often enough to carry spares and if there are any necessary hop ups for the truck. I know I'm going to need arms and the other obvious things. I'm sure this has been covered else where in this thread but this thread is really long. Thanks for you help.:nod:

People say the RPM bumper is a required hop-up, but I'm not so sure anymore. I have it on both of mine but a lot of folks don't have chassis breakage issues w/o it.

well i can now tell you that a 21t pinion will not reach the 75t spur. looks like a 22 would just make it.

Gearing Suggestions
 

Hey guys I just recently got a LRP SXX Comp. V2 esc and now im waiting on my Orion Vortex Vst Pro motor. Do any of you have experience or feedback with this set up? And what gearing are you running with. Ill be running my 2WD in a indoor clay track.

I agree , I haven't seen any breakages without it but the design of the brace and bumper getting the impact off the front tower has got to be a good thing . ( It does make a good carry handle too !)

what size motor is it?

Well after running a B4 tranny on my SC10 I decided to put the gear diff transmission back on the truck. I had an issue running a B4 tranny,
if I didnt have a stopper on the left side the dog bone would pop out.
When carpet season begins I'll put the B4 tranny back on.
I also run the rpm bumper and chassis brace, and RPM A-arms with the RPM bulkhead. My truck is well protected. I also had to get the GT2 hinge pins to make the rpm arms fit my truck.

LOL yep

You'll need to provide a rough track size, your exact motor spec (10.5, 17.5, etc.) and whether you'll be running any boost or not but I have that ESC and love it.

I'm just running 17.5/blinky stock but my settings are 3-6-0-10 (that'll make sense when you see the instruction manual) geared 26/75 on Trinity's D3 17.5 for an indoor track that is roughly 100'x35' big.

duhh thats what i forgot to add. Sorry. Its a 13.5T. Is the chart that comes in the AE 2WD manual pretty acurate or does it just depend on the track im running at? I have a temp gun so maybe trial and error...? But then again I dont want to buy several pinions or spur gears and not have use for most of them.

I ran a 13.5 for a while with 75/30 gearing and 30 deg of boost on the ESC. Never went beyond 150ish on the motor even after LOOOOOOOOONG practice runs.

Edit: Whoops, this is the SC10 thread, disregard my comment, it was for a B4.1