Anyone ever compare the two speed wise? I have been told the XZ set is slightly faster because of the helical cut gears but also slightly weaker vs the straight cut XR's . . . . just curious is all

I'm totally sure this has been discussed before . . . . lol

I heard helical is stronger and lasts longer because they have more contact area on gear, straight cut transmits more power. Or should i say less power loss through straight cut gear.

Not sure... But I just broke a helical cut gear and it destroyed the entire case.... trying the straight cut XR gears now

Straight cut = better efficiency = stronger = loudly = roughly operate.
Helical = silent = more axial pressure on ball bearing = more heat = bad efficiency.
All pure racing cars, bikes... have straight cut gears. Standard wehicles have helical cut mostly becouse of noise and smoth run.

Bingo !

Agree but aren't the xr gears larger. Thay would give them the extra strength?? Just askng

I keep hearing about people blowing up there drives. So I guess I'm next. Trying to take it easy and save up for something that will take the abuse. I'd rather buy something before mine go too. Sorry to hear about your drive.

Several guys are getting more speed out of the X/Helical cut gears and some are running thinner oil on top of that. Two race teams (that I know of) run X gears with better results.

Lets also throw in 1:65 vs 1:5 ratios. I was told the 1:65 last longer due to mechanical advantage. Somebody throw IMHO on that...

After breaking two sets of helical cut X gears I switched to the straight cut XR gear.

I lost 1-2 mph on the top end, and yes they are noisier.

My driving style has changed a bit too. I am much easier on acceleration and try to keep air time to a minimum..

I also am running a thinner oil. Torco RTF

So an old subject comes up . I know they have done improvements, upgrades and now offer 1.5 ratio. BMAX outdrives . What do you think or do you guys know anyone running them. Not looking for arguments