# Overforking an old/traditional XC frame?



## bob knox (Sep 7, 2017)

Full honesty, I don't completely know what I am talking about here. What are the issues of putting say a 140mm fork on an older 27.5 XC carbon hardtail that was designed for a 100? 

The bike currently has a 70.5dg head tube angle so slacker is what I'm after, but climbing technical chunky stuff is critical to what I ride out here on narrow NH trails. Would a 140 fork ruin that? I am constantly using all the fork travel because I am riding more aggressive trails. Yes, I need a new bike, but that's not in the cards right now. If I buy a new fork, I want to be able to put it on a future frame.

Thanks,
Bob K.


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## 834905 (Mar 8, 2018)

What frame? I wouldn’t do it personally because it’s going to ride goofy as hell. That’s just my opinion though. If you have the parts and everything is compatible I guess it’s worth trying.


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## bob knox (Sep 7, 2017)

Storck Rebel 7. My guess is you are right, it will "ride goofy as hell". If I understand geo charts correctly the "Reach" dimension will be off/too short. 

Bob


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## TwoTone (Jul 5, 2011)

Maybe and angle set


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## HandsomedanNZ (Feb 18, 2019)

TwoTone said:


> Maybe and angle set


This is what I'd suggest. 
Longer travel forks will just mess up your geo, if you're a XC rider and want the XC experience.


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## john1970 (Apr 11, 2009)

I would be cautious about placing a 140 mm fork on a frame designed for a 100 mm fork. In addition to the geometry I wonder if the frame was built and designed structurally to work with the extra 40 mm of travel? Usually one can get away with an extra 10-20 mm of travel, but an additional 40 mm might be too much.


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## 834905 (Mar 8, 2018)

OP says it’s an old frame. If it doesn’t at least have a 44mm head tube (I believe?) then an angle set won’t be an option.


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## bob knox (Sep 7, 2017)

John- That is an excellent point. I asked Storck if that would be a problem, but didn't get an answer.
Sounding like I should just keep riding and save for a new bike. 
Thank you everyone!


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## Dharmabum (Apr 18, 2021)

SingleSpeedSteven said:


> OP says it’s an old frame. If it doesn’t at least have a 44mm head tube (I believe?) then an angle set won’t be an option.


You can get a very nice 1.5* angle set for EC34 here:Login • Instagram


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## 834905 (Mar 8, 2018)

Dharmabum said:


> You can get a very nice 1.5* angle set here:Login • Instagram


Thought 44mm was the smallest they made. I hadn’t seen this before. Nice.


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## Shark (Feb 4, 2006)

+20mm is my general rule.

Sent from my SM-G991U using Tapatalk


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## Dharmabum (Apr 18, 2021)

SingleSpeedSteven said:


> Thought 44mm was the smallest they made. I hadn’t seen this before. Nice.


I have one on an old hardtail. Went from 100mm to 120mm travel. Angle set is very well done and I've had no issues. Shipping from Italy to Ohio took 2-3 weeks.


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## ladljon (Nov 30, 2011)

I got a 1 degree from Work Components for a EC34 and a 1.5 degree from rgbikecomponents. Use on Moots Zirkel 70.4 HT The 1.5 was too much for the fork I have. So used the 1 degree. I didn't add more travel, just a different fork.


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## r-rocket (Jun 23, 2014)

The bottom bracket will be too high. No real fix is possible.

The seat will be too far back. Might be able to slide the seat forward enough, maybe not. Might need a seat post with less offset to fix it.

Reach gets shorter. Might be able to use a combination of wider bars and longer stem, but it might still ride funny.

Your bike has a fairly short head tube length. If you cut the fork to fit that bike, it may not fit on your next bike if the head tube length is longer. It really won't fit if your next bike is a 29'er and you buy a 27.5 fork. Who knows if axle width, axle diameter, head tube diameter, or some other new crap will make a new fork obsolete by the time you buy a new bike. Or if the fork maker will even still support parts or rebuilds. I wouldn't spend a lot on a new fork, with the idea of swapping it onto a new bike in the future.

I agree with the decision to just rock that thing the way it is, and save up for a new bike. Use it as a skills challenge for downhills. Meanwhile, it is actually a good bike for climbing the narrow technical chunky stuff that you mentioned.


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## cassieno (Apr 28, 2011)

Use more air pressure if you are constantly using all fork travel. Look into if you can get a new airspring for your current fork / adjust the travel of your current fork.

Angleset (this will also shorten reach) and longer airspring (140mm is too much. You can probably get away with 120mm) is about all the money I would be willing to spend on that bike.


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## bob knox (Sep 7, 2017)

50th birthday came early...I couldn't resist the 20% off the Stanton 48hr frame sale. Picked up a Slackline. Hehe...now I have to save up for a fork. That will be almost 2x the cost of the frame.

Bob


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## Curveball (Aug 10, 2015)

bob knox said:


> 50th birthday came early...I couldn't resist the 20% off the Stanton 48hr frame sale. Picked up a Slackline. Hehe...now I have to save up for a fork. That will be almost 2x the cost of the frame.
> 
> Bob


That's a lot better approach than trying to make an XC bike into something that it isn't.

Congratulations!


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