Second run on new DH bike...

This bike aint gonna go as it is. It jumps really well, but at speed, the darn thing wanders and I end up pinballing both edges of the trail, which is pretty scary in my book. Did I mention brake bumps are like a frikkin deeath dance? The rear shock has a nasty habit of blowing through its travel too

For all my efforts, this is what I got.



I did have fun. I fought it as much as I could and got 6 runs in. I think I figured some of it out. The guy that sold me the bike was 160 pounds. I'm 175, and he said it was perfect for him. I'm guessing that info was wrong. I'm now looking to try a softer coil, maybe a blue or a purple Fox spring.

In the back, I'm going to try a harder spring. Its a 450 right now, maybe a 500.

Here's some pics from today...

 

:bang:

 

Maybe you need a longer stem? j/k

It could be a lot of things. Are those tires supposed to be good in dry conditions? No doubt it's going to have a different feel. Maybe ride it on trails you know until you get it dialed.

 

I'd add a little more compression to the back if that doesn't work try a stiffer spring. Also try slowing down the rebound. That made my bike get rid of the pinball feel and made the choppy sections a lot better.

Are you going up to snow summit next weekend?

 

Wait 450# spring? I hope thats a typo. I am 200 and run a 400# spring on the same eye to eye shock.

 

whatttttttttttt!!!!!!!! is that one of the trails there. Whats the name? Man Im stoked to get up there!

 

the rear shock is a bit of a conundrum.

ive run it with 4 out of 5 clicks of compression and it still blows through its travel. ive also tried the 500 spring, which i pulled off for today. with a 500, its at 22% sag. at 450, its at 30%.

i just picked up a high tune shim stack for the vivid r2c. gonna give that a whirl. i saw a leverage ratio chart for the 951 and it starts out at 3.55 and goes to 1.75. the average should land it in the medium tune, but some guys are having good luck with the high tune.

as for the front, which i think is primarily the reason it wanders, the front wheel dribbles like a basket with whatever rebound i put in. i think im oversprung big time. ive got 17% sag there.

i was riding with an str member and he mentioned that he had the xsoft spring. thats for 90-120 pounds, and he's 150. im going to try the soft spring, 120-150, even though im 175.

im planning to go to big bear in two weeks. likely will be bringing my am bike. the dh is going in storage until i get some parts together.

 

the 951 is weird. it uses really high coil rates. i did a bit of research and 450-500 are the rates being run by people in my weight range. some heavier guys have given up on their 951s due to non-availability of heavier springs.

i shoulda bought a session

 

If you did that to your hands after 6 runs, you need to relax. You're death gripping the bars which shows you're not very comfortable on the bike. How tall are you again? The 951 is a great bike. I know many people that rode one and they all ripped on that bike.

 

i would have ripped better on my am bike than the 951 set up as it is. im death gripping it because i was wrestling with it to go straight. Im guessing its not apparent that im trying to set up the suspension.

i bought a used bike and its entirely possible the last owner pulled the shock and the tune springs off the bike before it was sold. as it is, its all over the place. no biggie, just need to get it right. i have no doubt it will get there. the session though, with its enhaced single pivot would be a lot easier to tune.

even with death grip, i kept up with most, just not as much fun as having a tuned bike.

 

I'm a bigger guy (250ish geared up). I tried 500, 550, and 600 pound springs and the 550 is perfect. I noticed that it does way better with really slow rebound. I do have a DHX RC4 though.

If this is true then yes, you are way oversprung. Unfortunately though I've found most fork companies like to recommend way to high of rates for given weight. I have a Boxxer world cup and with the recommend spring rate (psi since it's an air spring) the sag was at 15%. According to Rock Shox my fork is now setup for a guy that weighs about 175-180 pounds yet this feels good to me and its sag is right at 28% (just shy of 30% mark).

 

That's Miracle Mile. Their second best trail on the resort.

 

after reading the manual (again) and a bunch of user experience, i think your onto soemthing with your suggestion. ill try it.

the manual specifically says the shock will feel slow in the parking lot. i also wont be shy with the compression next time. ima gonna pump that chit up.

over all, the rear felt great with the exception of bottoming harshly on high speed dips and berms. i think ill install the soft bumper as well, considering the 951 is known to ramp up in the end stroke.

thanks. now i need to track down a purple 40 spring that can get here in less than two weeks. calling fox tomorrow.

 

I have found that The Path keeps an assortment of Fox 40 springs in stock. I have a blue one that I don't use, if that's the one you need.

 

Hey Chris. I'm going to order the purple one first. If that doesnt work, I'll hit you up for the blue.

Thanks!

 

Leverage Ratio is probably lower on your bike.

 

I would recommend setting all the adjustments to something neutral and getting 1 or 2 more rides on it then mess with it . If you have never had a dh bike its going to feel off for a few trips.

Sent from my Galaxy Nexus using Tapatalk 2

 

What air pressure are you running in your tires, and with what tires?

 

muddy mary 2.5s dh casing, wired, evo vertstar compound

22 psi front 24 rear. the tires are rated down to 20.

i think i have the rear worked out. just tuning out bottoming on berms without getting too harsh on larger rocks. its a choice between a harder spring and less compression, or the current spring with more compression. the back feels great in 90% of situations.

the front, we'll see. just spoke to fox and they say i have a blue (med) ti spring (its colored silver gray), the previous owner tells me its a green (firm). i ordered a purple (soft). once i get the front sprung right, i should get it tracking well at speed, and then it will be a matter of a few clicks here and there.

 

Sounds like you're there with the tire pressures.

Keep in mind that Fox 40 forks have varied the damping over the years. Up through the 08 models, I always used the firm spring, but I found out that after I used an 09 for a while that I really needed to go to the med spring. I later learned that Fox changed the internal damping, and no adjustments would make a difference. I just set up my 13 with a medium, but don't have any time on it yet. So for whatever that's worth, just keep in mind that your forks valving may contribute to needing a different spring than some other guy with your same weight on a different year 40. If it's a newer 40, at 175 pounds, I'd bet you'd do pretty well on a soft fork spring, though if you're not used to DH bikes, it may feel odd setting so far into the sag.