Mountain Biking - fork travel and geometry distortion question

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100prcnt Marine
07-14-04, 09:14 AM
i am currently shopping for a new fork and narrowed my choices to 2 forks: the psylo xc 85-125 (is there an in-between?) or the marzocchi mx comp with ETA . the ETA comes in 2 different travel variations 100mm or 120. would the 120mm travel option distort my 2003hardrock frame to make an undesirable ride or is not that drastic .
thank you


PeterG1185
07-14-04, 09:27 AM
the 120mm's of travel will dramatically influence how the bike handles since it's designed around an 80mm fork, so i'd go 100mm's tops.

a2psyklnut
07-14-04, 09:38 AM
What model Hardrock? The Pro comes stock with a 100 mm travel and all the rest are 80mm. I compared the geometries and they're nearly identical with the exception being the standover (which makes sense).

I would think, seeing that, a 100 mm is fine.

Figure each inch of travel you increase, you slacken the head tube by 1 degree. So, if you jump up to a 125 mm travel fork, you'll slacken the headtube by another degree. Which will slow down the steering. This will make your bike handle better while descending, but climbing will suffer.

BTW, the Rock Shox is adjustable with the U-Turn and you can adjust it ANYWHERE in between.

L8R


a2psyklnut
07-14-04, 09:42 AM
Hmmmm, upon furhter examination, I'm guessing the geometry of the PRO is adjusted for the longer travel. Therefore unless you have the PRO model, I would NOT get more than 100 mm of travel. If you go to 125 mm you'll have a NET delta of 45 mm from the design, therefore about a 2 degree slacker headtube angle. That will probably change the feel of the bike considerably.

L8R

100prcnt Marine
07-14-04, 09:51 AM
Hmmmm, upon furhter examination, I'm guessing the geometry of the PRO is adjusted for the longer travel. Therefore unless you have the PRO model, I would NOT get more than 100 mm of travel. If you go to 125 mm you'll have a NET delta of 45 mm from the design, therefore about a 2 degree slacker headtube angle. That will probably change the feel of the bike considerably.

L8R
i do have the hard rock pro

a2psyklnut
07-15-04, 11:19 AM
Since you DO have the Pro, you could get away with up to 130 mm of travel without changing the feeling too much.

I have a 2001 Psylo and it's a great fork. I wore out my bushings, and I understand they've improved the durability on newer models.

Personally I didn't change mine out because I ended up buying a Marz. Z1. I feel the Marz is a much better fork all around.

I put the Psylo on my SS project bike.

Also, if you weigh over 200 lbs, I highly recommend the 20 mm through axle option! It helps reduce the lateral flex significantly.

I will probably not go back to a standard dropout fork, unless I loose 75 lbs. (Not likely!)

L8R

BlackDiamond
07-15-04, 04:49 PM
Since you DO have the Pro, you could get away with up to 130 mm of travel without changing the feeling too much.

This is going to be one of those rare times that I disagree with a2psyklnut. On your Hardrock Pro I would not go above a 120mm fork. A 120mm fork will feel much different on your bike than the 100mm that it came with. This will be especially true on the climbs or pedaling on flat ground. Putting on a fork with more travel will only help you on the descents. Also remember that a longer travel fork does indeed make the HA (Head Angle) more slack, but it also puts extra stress on your head tube.

a2psyklnut
07-15-04, 09:25 PM
I'll give you that BD, but he mentioned the Psylo with the U-turn and the infinitely adjustable travel. So, for climbing he could set it closer to @90 mm, then all around riding @ 105 (let's just assume), then if you're hitting a sustained downhill you could crank it up to 125!!!!

But yeah, 100 to 110 would probably be optimum - max.

L8R

100prcnt Marine
07-16-04, 08:02 AM
thank you guys this has been bothering me for weeks and i have learned alot. i am over 200 lbs 225 to be exact. i ride in an area thats considered very technical and have very ruff down hills. my first upgrade was to a rockshox pilot (BIG MISTAKE). i'm leaning more toward the marzocchi mx pro 120mm, i hope to order it before the end of the month and i'll post pics cause i know its the unwritten rule ..laugh out loud (no internet talk), and let u guys no how i like it or hate it.

thanks

100prcnt Marine
09-07-04, 08:42 AM
hi guys i'm back

i ended up getting a 2001 psylo race set at 125mm the fork works great. it did take some adjusting for the first 2 weeks but i overall i'm happy.

i notice the timing in steering was different but my control downhill improved vastly. going up hill is wierd because it always feels like i'm goingto end up on my back, so i just ordered the uturn upgrade kit and i'll install it this weekend and then i would probably leave it set to about 115mm.

thanks all for the input

hooligan
09-07-04, 02:37 PM
Wait...aren't the frames of all the hardrocks the same? Okay I'm talking about the 2004's. Are the sports and the comps different? Or are the pro's only? Because...I can't find any pro's!! :'(