501x Novak gtb 4.5 finally thermalled. Gearing comparisopns..

[Colinevan]

Unfortunately my 4.5 finally thermalled in the blistering heat at Bury this weekend. My initial gearing of a 16 tooth pinion vs 91 tooth spur resulted in the car losing its top end 4 mins into racing and running at half throttle until half a lap and then going back to full throttle etc.

I decided to drop to a 15 tooth pinion with the 91 tooth spur which helped matters as when calculated is the optimal 13.000 ( or there abouts )overall ratio as reccomended by novak.

However im wondering if that could be too low etc as the car was no where near as fast etc. Would going to a 17 make maters much worse etc?? Anyone tried experimenting.

My previous car ran a 5.5 on 96 tooth and 16 pinion and was fine.
This was replaced with a 4.5 which ironically woked best on the same gearing and i believe to this date is still on this gearing ( sold on).
New car runs obviously on 15/16 with a 91 and seems to run warmer than the previous older speedo. I will however state that yesterday was a very hot day

What is everyone else running on?

Col.

[chrispattinson]

I run a 4.5 Novak brushless, geared 17 pinion to 96 spur.

I have no overheating problems.

[mole2k]

I ran a novak 4.5R on a lrp sphere last weekend 17/91, it was a large track with long straights though. No real heat issues here 21c ambient temp. I didnt have the fan on the esc either.

[DaveG28]

Anyone got any pics of where they put the GTB in the Tam? Is it behind the steering servo?

[Lee]

I think a 4.5 is a bit nuts for bury I think your probably in the right ballpark on gearing, i think smooth driving will keep temps down more than anything though

[super__dan]

Ditto on a 4.5 being far too much for Bury, it's all stop and start (not in a bad way).

[Colinevan]

Just an update really guys. Unfortunately there was a problem with that motor. It just took a while to show through. I wont go into specifics as cml as being very good, but lets just say that things were not as they should. Thanks Col.

[501X Driver]

ColinevanJust an update really guys. Unfortunately there was a problem with that motor. It just took a while to show through. I wont go into specifics as cml as being very good, but lets just say that things were not as they should. Thanks Col.
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Will you share the issue.
I was running and had a wierd thing happen. I have a 84 spur and ran the 4.5 with a 18 pinion. Which is the wrong gearing but it ran without any issues. Once it was pointed out that it was not in the correct range I lowered it down to a 15 where it should of been ok. It had no punch and seemed really slow and ran at about 140f so I started moving back up on the pinion and it never ran cooler then the 140f and if I went back to a 17 or 18 it would thermal at the 3.5-4 min mark. And now it has that been worked to hard smell. It still runs for 3 min really well but after that it is crap.
So did I run it orginally and it broke in to that gearing and it would be ok or did something go bad with the wire or sensors and can be fixed or is it trash and I need to quit lugging it around in my box?