Piles

mes

It's my first wheeler in quite some time and I thought it would be normal for the amount of travel, but yes, it seemed a lot compared to my previous 2WD rides.

b1narych0ice

Hmm, so 2.50:1 vs 2.47:1, should be close enough to at least start with about the same gearing. I was running 26/78, so I should be able to try 24/72 on the new car to have the same ratio with less rotating mass.

Just for the sake of numbers:
(Spur/Pinion) * Internal Ratio = FDR
B64 FDR: (78/26) * 2.47 = 7.41
B74 FDR (78/26) * 2.50 = 7.50

So yeah, like a quarter-tooth worth of difference. I'll probably just try the 24/72 and see how it goes from there.

mes

And there is always the 75 tooth spur gear for more options.

I just added a gear chart to the wiki; minimum and maximum pinions were measured for 72 and 78 spur gears, 69 and 75 teeth values were calculated from the minimum and maximum sums of teeth. Mimimum and maximum pinions may vary between manufacturers, though.

Piles

mes

Today I had the chance to run a few batteries. What can I say, it is awesome! I always preferred 2WD on astroturf and carpet, but the B74 changed that. With just a few tweaks I was 0.6 seconds faster than my best 2WD time this year, and compared to my lap times with a friend's B64, I managed to shave off about 3 (!) seconds. Super easy and quick to drive, my best landing car ever. For the time being, I'll stick to modified, this is so much fun!

Kepner

What kinda track you running on? Lots of bumps? I'm tempted to do what you did but I suppose I should run the car before I make any changes. I tool noticed that there's a fair amount of change in steering when the suspension cycles.

In other news I was running it on the floor in the garage for a bit. So stinking quiet, except the splus 13.5 is very loud while coasting/breaking which I hope is normal. Even while rolling it by hand you can really here the motor poles jump from one to the next. Very strong 🧲 s

RazorRC

iTrader: (5)

Piles

enare

anyone posting before and after lap times, b64vb74?

enare

are you in the middle of your build razor? any pics of the shock caps? b64 had the bleeder screw...

trf211

Haven't gotten a b74 yet to test that but on our clay track we're still toe to toe in our mod class. With the b74 still in its infancy and the 64 plateauing, the b74 can only get faster.

RazorRC

iTrader: (5)

Just finished it except for paint. Here's what the inside of the shock cap looks like, there's no obvious hole that leads to the outside bleeder screw but it's in there if you look really hard (not visible in pic). Sorry it's a bit out of focus.

enare

I had a shock rebuild kit lying around for the b64. Here is the shock cap for this. Not sure how different it is but the hole is really small here as well.

FloridaST

iTrader: (4)

So how does the B74 stack up against the Xray XB4? I'm sure someone here has experience with both.