BMX - What Should I do?

Right now I have $250 in sponsorship money. I'm going to get one thing for my bike. I'm either going to get new rims(just rims) or new cranks. I don't really know which one would help me more so you tell me.
Cranks-
Black Profile 170mm w/ Profile hop-up kit
or
Rims-
Sun CR-18 1.5"

By the way, both parts I have right now are stock and my cranks are chromoly, but it feels like they flex a lot and they're also too long.

I would go with the crank's. How do you have sponsorship money, what it is.

cranks

for $240 I was able to get the profile raws, hop-up kit, and FSA Ti spindle. That was a huge weight reduction, and my recommendation for you.

I'm not going to get a Ti spindle. I'm just getting black Profile BMX cranks with the hop-up kit. It comes with all the cups and bearings and everything right?

yeah, the bearings are essentially the cups, but it does come with everything that you need.

Good for you mini! I am working over a sponsorship proposal right now. I don't need any bike parts. I'll probably just use the money towards racing fees. Is the $250 in addition to covering your racing fees or is it a flat amount? You are far too light to need a Ti spindle in your bottom bracket. Don't spend that kind of money on a spindle.

Yeah, it's great having a sponsor. They are a local rental company. It is a flat amount as I get $125 a month. I can use the money for anything really, at the beginning of the season I got a new uniform and in August I used it national regristration which was $115, whatever I don't use goes toward race fees.

Just as an FYI. Weight reduction in the wheels. (especially the rims) makes much more difference and benefit than the crank spindle. The rims not only have mass you need to transport but a MUCH higher rotational moment of inertia to overcome between standing still and full race speed. Basically the larger the spinning radius.... the more benefit you will get from weight reduction.

Thanks, Lancerbob. I would just get the cranks with smaller rims than the cranks with the Ti spindle. But I'm just getting one thing so I'm going to go with the cranks.

I'm going to assume "No", but I'll ask anyway: Does anyone run singlewall rims to shed rotational mass?

I'm going to assume "No", but I'll ask anyway: Does anyone run singlewall rims to shed rotational mass?

I weigh 205 lbs so my answer would definitely be NO! :lol: I can't imagine a cross section that is single walled for any but the most featherlight of riders.

How about these Velocitys?:

How about these Velocitys?:


Road rims?

Those are 20" rims.

Yeah, they make FMF rims and some Sun rims like that.