GT Grade (1st model, Alloy) need new fork
 

Hi everyone, anyone could recommand a fork for Gt grade ( 1st model , alloy one) broke mine and love that bike so much and can not afford to buy a new bike at the moment
thanks

Your fork was a tapered steerer 15mm thru axle with 45mm of rake, post mount brakes, and 395mm axle to crown.

You should list what you want to spend because forks can cost $200 or $600. No point in suggesting forks that are way above or below what you want.
The 15mm thru axle and post mount are more dated features, but there are workarounds for both since many(most?) name brand gravel forks now come with 12mm thru axle and flat mount.


There are forks with about 45mm of rake and about 395mm a-c length, which are the two important measurements to make the new fork have the same geometry as your current fork.

493mm is quite long for a rigid fork. Wouldn't hurt to go a little bit short. You'll dial up the head tube angle a little and speed up the handling in a good way.

https://www.theproscloset.com/produc...bon-disc-black

395mm a-c measurement. I have no idea why I typed 493- that would be a HUGE fork!
thanks for pointing that out, i edited the initial post.

Lmao, that sounds much more releastic. Imagine how the bike would look with a fork that long. That's probably just about the shortest you can go whilst using the 700c rim.

To be honest, unless we're taking about a gargantuan sized frame, the handling would be better using a 26" rim and even going down to 385mm for the ATC.

Have you checked with GT to see if you can get an OEM one from them?

how did you break your original fork?

how do you like the current handling around tighter turns? is it the ideal balance between steering response and stability? or do you want to speed up the handling a little bit?

395 is very common for bikes like this.

The specs I found is that it's tapered to 1 1/4", which isn't too common. I expect it would be easier to go to 1 1/8" and a conversion headset

None of this is true

better off doing this

May you explain your reasoning behind this? Lowering the front end of the bike = steeper head tube angle. You'll be lower to the ground. Switching from a 700c rim to 26" will lower the front end by another inch.

unter may be patient and explain why your idea is wonky, but based on your comments in the general forum when it comes to frame fit and geometry, you should be banned from giving out advice.

Going 10 or 20mm shorter is very unlikely to negatively impact the handling of the bike in any way. Nearly all bikes seem to be all jacked up these days, especially if they have front suspension.

The alloy versions had a QR fork, not a thru axle. The taper is also 1-1/4 to 1-1/8, which I understand is a little unusual. Definitely worth contacting GT to avoid potential fit problems.

This is wrong too. Seriously, Unterhausen and myself both build bicycle frames and have some knowledge and experience with bicycle frame geometry and the effects of changing the axle to crown length on an existing frame. Changing the axle to crown height has an effect on almost every other part of the frame. Making the fork shorter will make the head tube angle steeper, shorten the trail, lower the handlebar position, make the seat tube angle steeper and lower the bottom bracket. All of those will negatively impact the handling and fit of the bike.

I have seen your other threads about frame geometry and almost all of your assumptions and conclusions are incorrect. Please stop giving advice about frame geometry.

using a fork that is too long is even worse. You're placing tons of stress on the fork itself as well as the head tube and headset.

My point is, that if you are able to find the right size fork for your bike (great) if not, a slight deviation in fork length isn't going to cause you any problems whatsoever. I've experimented with forks enough to determine that if forced to choose, I'd rather pick a bit too short than too long. Only going like 40+mm too long can cause you real problems. The shortest fork you can find out there is 385mm which will work perfectly fine..

395mm A-C is an extremely common fork now, there is no reason to change. Especially since the OP likes his bike and it doesn't sound like he wants to experiment. Let's do a thought experiment, if a longer fork was going to have structural problems, ,would they sell that longer fork? It's certainly not going to affect the frame. I think we would all appreciate it if you would stop disrupting the thread.

Fair point. But..

Are you seriously telling me that every single bike is designed around one size fork? They are not. Using a longer fork on a frame designed around 385 or 395mm will slow down turn in and reduce front tire grip. The extra leverage being placed onto the fork due to the jacked up angle of the head tube places tons of undue stress onto that longer fork - which is not designed around this sort of geometry. The end result is that the fork bends backwards to physically adjust the rake back to where it should be.

Ask me how I know. For example, the Chiru Kegeti comes with either suspension or a 495mm suspension corrected rigid for. How do you think a bike designed around 495mm versus 395mm would look and feel? Now picture swapping their forks and comparing..?

I think that this thread is related to forks. I would appreciate if you could explain what exactly it is here thats so important which I am disrupting with my conversation about how forks alter frame geometry. Next, It would be most meaningful if you explained why you think I'm wrong in a non condescending tone. And please don't tell me you can use a longer fork without a problem after telling me that going 10mm shorter would be a problem. I have literally bent 2 in a row because I tried to make due with whatever I could find at the local Bikehub for my GT. They were only 25mm too long, but being only compatible with a 27-28inch wheel meant that the extra inch in height above the front axle = 47mm in extra height which bent the fork. Again.

I don't feel like you are participating in a good-faith quest for knowledge, and are giving bad advice without any relevant experience. In any event, dsaul already explained it to you. I have no idea how a fork that was only one inch longer than stock would bend. Why wouldn't it bend on the bike it was built for? It doesn't sound like it harmed your frame.

Here it is again. If a replacement fork is longer, you end up with more trail and more flop. Some people like trail, it feels sure footed on loose surfaces. I don't think anyone likes flop. And the extra trail may be too much, making steering sluggish and climbing unpleasant. Shorter forks will be lower trail and the steering will probably be a lot quicker. Unpleasantly so. Not to mention the loss of tire clearance. I don't think there is much more to explain. It's one of those things where the best advice is not to change anything unnecessarily, especially if you like the status quo.

I don't know, 1 1/4" seems extremely common to me; many current road bikes use this size including the new Grade.

I was surprised at how many 1 1/4" steerer forks there were. So maybe the OP is in luck. But we scared him off.