Replacing fork

Gavin

I want to replace the fork on my Banana bike, so as I can mount a disc brake on the front. The bike is somewhat old, and has a quill stem of 21.1mm. Does this determine the diameter of the steerer tube ?

I'm guessing I can probably use a 1" fork to replace the current one.. How can I check this, just measure the width of the current steerer tube ?

CheGuedara

Sounds like a 1 in steerer alright.

I think you'll have to look for a fork with a 1 inch threaded steerer or a 1 inch unthreaded steerer and getting a new headset. of course then you're looking at a new stem too...

Gavin

Yeah have a spare stem, so don't mind getting a headset. Proving difficult to find a 1" fork with disc mounts!

CheGuedara

Getting a 1 inch fork full stop is difficult these days without being specific about anything else - I know eXotic cycles do a carbon disc compatable rigid fork but can't say I know how good or bad they are.

On the suspension fork side I think looking down the RST or Marzocchi - think they do (or certainly did 1" steerers on some fork models

kona

Handy enough to get 1" steerer tubes. You can get the threads cut into them too in your LCB.

abcdggs

kona wrote: »

Handy enough to get 1" steerer tubes. You can get the threads cut into them too in your LCB.

LCB?

CheGuedara

Get a fork with 1 1/8in steerer and swap it out for a 1in one is it? Didn't think you could do that with most forks

kona

abcdggs wrote: »

LCB?

Long centre branch ....a type of car exhaust.

i should have typed LBS. Damn abbreviations

kona

CheGuedara wrote: »

Get a fork with 1 1/8in steerer and swap it out for a 1in one is it? Didn't think you could do that with most forks

Not sure if thats even possible.

SR suntour do disc mount 1" suspension forks. Most **** bikes have 1" steerer tubes too.

Gavin

Yeah, looking for a rigid fork, which again narrows down an already small range.

ednwireland

can you still change steerers on pace forks pace rc31 are the rigid ones

(i have some old pace rc35 with interchangeable steerer tube has 1 1/4"in there at the moment)

hmm withdraw that looks like theyve stopped making them (pace have been ruined by dt swiss buying them !) still have them on the website but 1 1/8" only

'68 Fastback

I'd look into this more if i were you Gav, will the old school Banana frame withstand the braking forces of a disc? You might end up tearing the front end off your bike.:(

kona

'68 wrote:

I'd look into this more if i were you Gav, will the old school Banana frame withstand the braking forces of a disc? You might end up tearing the front end off your bike.:(

Why? If its a lugged steel frame id say its stronger than many BSO that have discs.

'68 Fastback

for a start, I doubt Gavin is going to install the type of disc found on a BSO. secondly, ive seen the front end of a early 90's cinder cone damaged by the ill advised use of discs. i reckon a late 80's and not even a reynolds built, road bike, designed for use with late 80's calipers, would possibly have trouble with the braking forces of a proper disc setup.

on the other hand, the front end might not even feel any stress at all seeing as how a 700/23 will probably loose all its traction if you use a disc. this might be why the manufacturers dont put discs on road bikes.

TinyExplosions

'68 wrote:

on the other hand, the front end might not even feel any stress at all seeing as how a 700/23 will probably loose all its traction if you use a disc. this might be why the manufacturers dont put discs on road bikes.

I suspect it's more for weight reasons than the tyre size.... there's plenty of hybrids out there running 25's that have disc brakes

'68 Fastback

TinyExplosions wrote: »

I suspect it's more for weight reasons than the tyre size.... there's plenty of hybrids out there running 25's that have disc brakes

You're probably right. But seriously, I'd check the frame out. Mountain bikes accross the board were heavily beefed up at the head tube when the whole disc brake phenomenon took off. Granted, this was also to deal with the increases in suspension travel, but the bananna frame has lugs, not gussets. It'd be a shame to wreck a nice frame.

kona

'68 wrote:

for a start, I doubt Gavin is going to install the type of disc found on a BSO. secondly, ive seen the front end of a early 90's cinder cone damaged by the ill advised use of discs. i reckon a late 80's and not even a reynolds built, road bike, designed for use with late 80's calipers, would possibly have trouble with the braking forces of a proper disc setup.

on the other hand, the front end might not even feel any stress at all seeing as how a 700/23 will probably loose all its traction if you use a disc. this might be why the manufacturers dont put discs on road bikes.

I doubt he is going to be slamming on at every opertunity. Most people break at the back with a small amount at the front.
Without seeing the cindercone(which I take is almost 20 years old) I wouldnt be able to comment, but I'd Imagine that there was other forces at play than that of a disc brake, main one being the age, a old MTB will have taken waaaay more abuse than a 30 year old racer.

Ive also seen 2005 stinkys shear at the headtube, plenty of vids on youtube. These are beefed up too. Its more to do with the rider than the components IMO. Steel is going to be quite strong, regardless of who makes the tubing. The weak spots are the welds, and If im mistaken, Gavins bike will be lugged with a braze holding it together.

Gavin

I have misled you all. My bike is not a genuine Raleigh Banana road bike. It is a 90s Raleigh Max mtb, which is all yellow, thus I call it the Banana. It's most confusing.

'68 Fastback

Ahh! The head tube is definately going to fall off then, but that rear wheel looks solid as a rock;)

TinyExplosions

Wow, that rear rack looks ghey