Seeing as this forum can answer just about any question on any topic, I thought I'd try this one regarding my mountain bike.

I have a mountain bike which currently has rigid forks. The steerer tube is 1" diameter, 145mm long and threaded.

I also have a pair of Rockshox suspension forks but the steerer tube is 1 & 1/8" diameter, about 200mm long and threadless

Can I change the bearing races on the headtube to accept the larger diameter and threadless steerer tube suspension forks or will the headtube diameter be too small?

I know that I'd also have to change the handlebar stem configuration too but if the headtube on the frame will take the larger diameter forks, it should be quite easy.

Anybody know?

Phil

[Edited on 2-3-09 by Hellfire]

I very much doubt you would have enough space in the frame to fit a 1/1/8" headset.... so no.... I dont think its going to be possible...

Unless you have a weirdly oversized head tube...

^^^ yep same here. I don't recall ever seeing 1 1/8 inch bearing race to fit a 1 inch head tube.

will post your query on a bike chat forum.

Depending on the thickness of the steerer tube, you might be able to get it milled out to accept a 1 1/8" headset. Obviously this will have the effect of weakening the tube front of the bike so proceed with caution. Personally i would be very wary of doing this - especially with an aluminium frame.

[Edited on 2/3/09 by Paul TigerB6]

cant be done. worked in a bike shop for 3 years and customers were always wanting to put new forks in old bikes.

milling out frame is not possible. welding/brazing in a new headtube might be - but is it really worth it? a different frame would be easier

and yes the 1 1/8 forks will be A-head system so you will need expensive adapters or a new stem to attach handlebars.

will

Mr Fire:

Even if it were possible, it would be cheaper and easier to get a new or used frame with a 1 1/8th steerer from e-bate, even including the cost of a new bottom bracket and (possibly) a new stem.

But I wouldn't bother with suspension if I were you, unless you ride down talus fields, rocky stream beds, or do lots of "x-treme" downhill MTB racing. Stick with the rigid forks - suspension forks on recreational mountain bikes are just there to convince you to spend money up front, and then spend more money when they break. Sort of like all the electronic crap that's stuck on cars.

quote:

---

Originally posted by Hellfire
Seeing as this forum can answer just about any question on any topic, I thought I'd try this one regarding my mountain bike.

I have a mountain bike which currently has rigid forks. The steerer tube is 1" diameter, 145mm long and threaded.

I also have a pair of Rockshox suspension forks but the steerer tube is 1 & 1/8" diameter, about 200mm long and threadless

Can I change the bearing races on the headtube to accept the larger diameter and threadless steerer tube suspension forks or will the headtube diameter be too small?

I know that I'd also have to change the handlebar stem configuration too but if the headtube on the frame will take the larger diameter forks, it should be quite easy.

Anybody know?

Phil

[Edited on 2-3-09 by Hellfire]

---

Coming at it from the other angle....

Is the Rockshox steerer tube removable (clamped) or pressed in?

If it's clamped in you may be able to replace with a 1" threaded steerer tube and pack out the difference with a shim. Then reuse your existing bearings and stem.

Ultimately a new frame would be the best option, but if your current bike has a 1" threaded steerer tube and rigid forks then the chances are it has canti or maybe V brakes, a threaded bottom bracket etc which means the new frame route might cost you a lot more in replacing all the other parts that hang off it - oh and the frent mech probably won't fit either

Never simple and like most industries, they keep things changing to keep you spending money

Oh well. Probably gonna be easier to buy another mountain bike if I want front suspension. The steerer tube is a one time press fit so not really interchangeable.

Having said that, I could always sell the Rockshox and keep an eye out for suspension forks with the correct length, 1" diameter steerer tube.

Phil

I know little about cars, strange as it is, but I know a lot about bikes, having raced them for years, til last year. Do yourself a favour and splurge on a new bike. You will like it a lot more than modding an old 1" steerer tube to fit an old fork.

I don't do enough cycling to justify buying a new bike and even if I did, I still wouldn't buy new. Second hand is good enough for me. Let someone else get hit with the depreciation.

Phil

Back in the day when I raced mountain bikes, I had an XT equipped Orange P7 with rigid forks. I came off it quite badly once, fracturing my wrist due to the front end getting stuck in a small rut. I convinced myself that a pair of suspension forks would have popped out of the rut and saved my wrist, so i spent the best part of 400 quid on a set of Pace carbon forks (RC35) they were monumentally crap and put me off suspension for a while, until the bike was nicked and replaced with a Marin Rift Zone full sus rig. AWESOME, back to being a convert Now I dont race, and ride a Specialized FSR, love the supple suspension, I wouldn't go back to rigid now.