[skatetokil]

I know that perhaps my desire to race on my trailbike is misguided, but I would like to know if anybody has any reccomendations for parts upgrades before I try it (or would like to try talking me out of it). I have never raced before, but I like to go fast and signing up for races at mountains in my area is often cheaper than paying normal lift prices. The courses I plan to do this season wont be super technical.

I almost certainly need a new fork (running a stiff psylo XC right now), so does anyone have any reccomendations for something that won't completely foul the geometry? Shiver SC? JrT? Should I go 20mm thru axle or keep my current QR XT disk rhyno lite setup? How about bumping up from the 160 mm disk on the front? Everything else is fairly beefed up except maybe for the cranks, but that's easy. Got an spv 4 way coil that should hold up fine. And remember, I am a starving college student, so no super high-budget suggestions.

 

[Kevin]

Your best bet is probably to sell the AC and get yourself a low budget DH bike. Or maybee something like a bighit or a Ironhorse.
If ur gonna use the AC youre gonna have a lot of costs on a regular base wich will make it more expensive in the end.

 

[rubbersidedw22]

I have and ac 2 with and shiver sc on you might want to put a jr. t on your bike. I ride at plattekill, mount snow and other trails around my area and I bottom the fork out. Don't get me wrong its a good fork. You might also want to put a short cage rear derailer and a chain guide on. If you are from the east cost there are a lot of rock garden and what not. The only other things if don't be supried if something break. Try racing and if you like it you will def. need to up grade your bike.
happy trail

 

[konahucker43]

id say get a sherman break out + so i wont kill your geometry. might want to put on like 2 inch risers, really short stem and some nice downhill tyres

 

[binary visions]

Couple pieces of misguided advice here.

A Breakout+ is for a 1.5" headtube, which the AC doesn't have.

If you bottom a fork out, it's setup wrong. Period. There are occasional exceptions for defective forks but the fact of the matter is, if your fork works, and it bottoms out all the time, it is user error in fork setup.

Anyhow... I'd say that at the outside, you might want to upgrade your fork to a higher quality 6" (or 5" if you want to stick with the current frame angles) single crown w/ 20mm axle like a Marzocchi Z.1 FR or Sherman Firefly. That's only if you can spring for the fork, hub & rebuild of your wheel, though.

You'll definitly want a new set of DH tires - that will make one of the biggest differences in your ability to get down the trail. A shorter stem would be nice, but is not really necessary unless you can get an inexpensive one.

However, you should recognize this for what it is - a band-aid bike for when you can't afford a DH bike. You may end up wrecking your frame simply from the high-abuse wear you give it (not necessarily from the frame snapping in half). The optimal solution is a purchase of a used DH bike - but if you don't have the money, you don't have the money, and that shouldn't keep you off the trails

Have fun!

 

[Frankenschwinn]

You can race anything you have. you may not be as successful but you have to start somewhere. Don't put too much money into making the AC a DH bike.. It will never be one. It is a good start though and should let you taste what DH racing is all about. I have put together a 04 V10 with a 7" travel super t and Deemax wheels for around 1500.00 - 1700.00 It has taken patience and a lot of looking for deals that would suit my needs but it can be done. 20mm thru axle is going to be the best thing. See if you can find an older (2001) super T. Oh yeah, like the previous person said. get the widest tires your frame will support.

 

[BMXman]

Couple pieces of misguided advice here.

A Breakout+ is for a 1.5" headtube, which the AC doesn't have.

If you bottom a fork out, it's setup wrong. Period. There are occasional exceptions for defective forks but the fact of the matter is, if your fork works, and it bottoms out all the time, it is user error in fork setup.

Anyhow... I'd say that at the outside, you might want to upgrade your fork to a higher quality 6" (or 5" if you want to stick with the current frame angles) single crown w/ 20mm axle like a Marzocchi Z.1 FR or Sherman Firefly. That's only if you can spring for the fork, hub & rebuild of your wheel, though.

You'll definitly want a new set of DH tires - that will make one of the biggest differences in your ability to get down the trail. A shorter stem would be nice, but is not really necessary unless you can get an inexpensive one.

However, you should recognize this for what it is - a band-aid bike for when you can't afford a DH bike. You may end up wrecking your frame simply from the high-abuse wear you give it (not necessarily from the frame snapping in half). The optimal solution is a purchase of a used DH bike - but if you don't have the money, you don't have the money, and that shouldn't keep you off the trails

Have fun!

I couldn't have said it better...D

 

[Darryl]

I rode my AC as a freeride/DH bike for almost a year with a 5" fork. Me and the bike got the living shiz beat out of us. After pouring some money into upgrades I finally bit the bullet and got something beefier, never looked back. You'd be a lot better served long term to just make the investment.

 

[skatetokil]

Well, thanks for the input so far. I already have it set up to decend as rapidly as possible. I'm running panaracer fire FR 2.4s which hook up well here in socal, I've got a downhill stem and some titec hellbent risers on there. Gravity has always been the name of the game, it's just that where I live, I have always had to pedal to get up the mountain. Thats where the 4 bar - spv - trailbike thing came in. I really like the bike (it is starting to feel like a part of me), but I had been thinking about going to a new fork anyway. The only question was whether the fork was going be beefier or just higher quality.

 

[Bacardi]

How much do you weigh?

Tires might be the biggest factor for you right now....and handling skills (braking, turning etc.)
There are plenty of tires on sales here (single-ply, 2-ply, 2.3s 2.5s all on sale). You could run thin inner tubes (2.1ish) with slime sealant, and obviously with single-ply tires run higher pressure (depends on your weight, ability to not hit objects)

5" 20mm front fork might help, and bigger rotors might too, but I wouldn't put hundreds $$$ into it. Plus if your broke you can't race too much anyway.

 

[corey_rideDC]

i got lots of good advice on the same situation in this thread: http://www.ridemonkey.com/forums/showthread.php?t=108539

good luck!

 

[The Rose]

I have an AC which I use as a dh bike. I run a 24 inch rear wheel, sherman slider plus forks and a E-13 chainguide. The bike works pretty well and for 2 seasons doing downhill it has survived with but a few dents and scars.

 

[thaflyinfatman]

Just race it a couple of times, if YOU feel like anything isn't working as well as it could, THEN worry about replacing it. Heaps and heaps of people race those over here, they work fine. Like BV said, you may end up killing the frame, but that's all part and parcel of the sport IMO. Just ride it!

 

[mack]

How much do you weigh, you dont need a new bike.

If you weigh beneath 140 and arent overly tall, it is totally doable. Get a new fork for sure, somthing with 6+ inches of travel, if your light you can get away with a QR. a bigger rotar size will also be helpfull.

have fun...

 

[Spitfired]

I rode my old AC Air at Pkill with a monster T.

It worked.

I didn't place very well.

 

[NotQuiteJdm]

This year will be my first at DH racing, I found a RM7 on MTBR.com for $900 shipped complete..used by an older man for XC, he had it down to 37lbs w/ SC shiver and El Jefe but I knew w/ all the lighter weight stuff it wouldn't be able to handle the abuse Im going to put it through. So far ive put Truvativ DH cranks, Sun SUV wheelset, DC Shiver, 8" juicy 5's, SIC bar/stem combo, FSA pig DH headset, Weyless pedals and some nice Michelin tires on it..total cost under $1000. You've just got to look around for the good deals man, I go to school part time so I sorta know what its like but I suggest looking for a cheaper DH/FR bike like a big hit or sgs.