Mountain Biking - Fork and bike measurement question

Hi all


I did some measurements on my bike before checking bike shops for forks (z1 dropoff and MXproETA). My current setup is with a fork of 475mm height (dropout to headset). The Mxpro is 478mm and the Z1 is 518mm . I have put a 40mm book below my front wheel to check how the bike looks with 40mm rise up front and it looks pretty weird. Also i realised that i am going to need a new hydro brake cable for my XT disc front brake (650mm cable now which will become pretty streched with more 40mm in height.). All i am asking is if i am going to ruin my bike with 40mm of more height in the front and if the MXpro is such worse that the Z1 .(AggroXc/mild Dh/Steep descents/Lots of climbing on my rides) .Sorry for repeating the forks subject but i just stumped on this new issue. 40mm more height.Brake cable may need change(+40$), should i opt for the MXpro?

40mm is a lot. I usually don't recommend changin the front end geometry more than 20mm. The bikes headtube wasn't designed for stress from that angle and the bikes geometry wasn't designed to ride like that. I would email the bike company and ask them what they think. 400 may not seem like a lot but it does change where the stress is applied on the headtub.

40mm to your riding will feel very different like I explained before. But in a few rides you may not even notice...but even the MX will seem like a dream over a 3 inch fork you are currently running.

True my friend. i have never thought of the stress angle change on the head tube. Are there any restrictions on what forks to fit to each frame? And i dont mean geometry/riding restrictions...i mean fatigue and stress restrictions. The main dream difference i expect to see with the MXproETA or the Z1 is quality suspension and lots of stiffness since i am running a 4inch Axel noodle. By the way...2003 MXpro is 2002 Z1 which means same crown and 30mm stanchions which i presume is ultra stiff and durable for aggro xc and mild dh.

The only way to know that is to speak with the company and ask them about there welding practices. IKnow on my bike I can jump to 6 inches (40 mm change from stock) because the headtube is overbuilt.

If you are running a 4" axel ... the Z1 is only 5" which is around 25mm which will be fine...unless the z1 is slightly longer the 5" and the axel is slightly less than 4...Its only a 30mm difference not 40mm :)...Just check with the makes of your bike to make sure the headtub is still strong enough and warrantied...if it is get the z1 :)

BTW the 2003 MXpro is equal to the 02 z1 dropoff. But with extras...the z1 dropoff had a lot of issues with breakages however in 2003 they overbuilt the crowns so the entire 03 line of forks should be much stronger than 2002. :)

So far i have found no way of contacting specialized. i have the 2003 rockhopper. Anyway. The 2003 Z1 is 518mm height while my axel is 475mm in 4" setting. The MXpro is also 480mm. so the difference in height is 43mm . The travel difference is 25mm however...but i was talking to total height difference. Since i cant contact specialized got any ideas?

http://www.specialized.com/SBCFAQ.jsp?a=b try posting your question here...

Don't forget marzocchi may have a different sag height then your axel. Thats why people never check actual length of fork but only referecne travel itself...never even thought to check that though :)

I popped them with the question and i am waiting an answer. However on one other user who had a 2001 rockhopper they told him that the bike was designed around an 80mm fork and a longer travel one would endanger the frame. I really hope that the 2003 series is designed around an 100mm fork (since the axel is 80-100mm fork) so that i can fit the Z1. If i cant i must do with the MXpro. i hope its equaly good to the Z1.

it is better than last years Z1 dropoff...definately.

Wow the guys at specialized are amazing. They replied within the hour.
They said the following :Thanks for the questions. The frame is sturdy enough for a 5" fork, as long as
you use it under normal riding conditions. Thanks again.
So mael ...i should go for the Z1 then.... but unfortunately i ll need a new brake cable.

I would go with the z1...and yes it is worth it :)...

Btw what bike do you ride my friend?

Kona Roast...some changes to it from this picture. I put a bash gaurd back on and broke the pedals...

One of the fork / front wheel.

I also bought a raceface stem...so this is in place of the kona :)

nice bike. impresive and rather similar to mine in philosophy. It seems that trailriding bikes are wining ground over specific dh/fr/xc bikes.

Hmm interesting idea but I can't really agree completely...while I do see you point when I know my skills have developed enough to justify a fully I will strip this bike and buy a good dually. I will then turn this into a dj/urban bike :)...

Can't wait to see pics of your bike when its complete...

Well my philosophy is to have a good hardtail frame...not race xc but kind of overbuilt trail frame like the rockhopper or the stab. Then throw money on quality equipment where it matters. I dont like duallies, and i wouldnt even like the best dually to have...they need much care and service on the bushings/bearings. Anyhow...here is a pic of my bike ...it lacks a new addition in the name of Raceface Deus stem.