Changing from suspension forks to ridged

[Tank63]

I have a Scott P3 hybrid with suspension.
I have never used the suspension since owning the bike as I have locked the suspension so it's ridged. I'm more of a touring guy just cycling and plodding along and very rarely go off road. My question is would it be better to change my front forks to a ridged set and safe some weight? Is it possible to change a bike designed with suspension to a ridged bike?
Welcome people's views.

 

[raleighnut]

Yep, it is pretty easy, all you need to do is work out the length you need and what steerer set up you have fitted.
the correct length is measured from the bottom head race to the axle/dropouts less about 15mm (when you sit on a bike the preload should be adjusted so that the forks slightly compress, that is where the head angle/height is optimised.

 

[ufkacbln]

You need to have a look at the fork "shape"

There are elements of fork shape that affect handling

You need to make sure that the replacement matches

Google "bicycle fork geometry" for more info

 

[Cubist]

Both the above posts have it. In order to keep the geometry the same you need to measure the effective axle to crown height of your sagged fork and check that there is no difference in dropout offset between the two. To be fair they won't make much difference if you have been riding round on a bike with the fork locked, especially if it's for road use.

 

[ChrisEyles]

I did this a little while ago (on a 90s MTB rather than a hybrid, but same principle). From the research I did most forks tend to have similar offset distances, but the axle-to-crown distance can vary from 390mm (26" rigid fork) to 450mm (or even more for long travel sus forks). In theory going to a shorter fork will make the handling sharper/twitcher while going to a longer fork will make it more stable/less responsive.

However.... I wasn't able to find an exact match for the axle-to-crown distance of my fork so I changed from 445mm (sagged sus fork) to 425mm (rigid fork) and the difference in handling didn't seem so great to me. Perhaps a tad sharper, but could have been just my imagination, and definitely not as big a difference as the lack of flex from the old sus fork. So I wouldn't worry overly much about getting a perfect match on the axle-to-crown length, an approximate match should be fine.

Finally, make sure you get a fork that's compatible with your headset (threaded or threadless). Should be obvious, but a friend recently bought a threaded steerer tube fork for his MTB with threadless headset and the swap ended up being a tad more expensive than he'd reckoned.

 

[Milkfloat]

I have been looking for a cheap rigid fork for my 90s MTB that has been relegated to a utility bike. I find that steerer length is easy to find, but axel-crown specifications are rarely listed. I am just have to take a punt on these http://www.ebay.co.uk/itm/162039498506

 

[ChrisEyles]

I bought mine off a chap on the retrobike forum, which has a pretty good classifieds section for retro MTB parts.

Most of the generic 26" rigid forks I found specs for online tended to be 395mm A2C distance, which is a bit short if it's intended as a substitution for a suspension fork. Always worth firing off a quick email to ask if the seller can measure it.

Good point @Milkfloat - definitely make sure the steerer tube is long enough before buying (won't be a proble on a new fork, but a cut-down 2nd hand one might be too short - I had to remove all the spacers under the stem to get mine to fit).

 

[Globalti]

I did this when I got fed up with my Rebas leaking oil and sent them back to the importer. I bought a set of rigid carbon eXotic forks from Carbon Components and they rode so smoothly that when the Rebas came back I put them straight on Ebay.

 

[Ajax Bay]

In theory going to a shorter fork will make the handling sharper/twitcher (sic) while going to a longer fork will make it more stable/less responsive.

OP - you're considering installing a shorter fork. Roughly, every 18mm shorter means your head angle will increase by a degree, and a steeper head angle results in 'quicker' handling.
This article deals with it and suggests that more than a cm difference and you'd notice it. Since you're "more of a touring guy just cycling and plodding along" you will need to take into account whether you want 'twitchier' handling. However, Chris reduced his by 2cm and his experience:

Perhaps a tad sharper, but could have been just my imagination