Fork, stem height question

Shop deals on ebay
Advertise with us
Bike Wall
shop deals on amazon
Rat Rod Bikes Bicycle Forum

Help Support Rat Rod Bikes Bicycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
us56456712

us56456712

Pro Member
Joined
Sep 17, 2013
Messages
4,217
Reaction score
9,130
Location
The middle of the Upper Peninsula of Michigan
Rating - 100%
3   0   0
I'm building a carbon, alloy and titanium mountain bike to accommodate my age (72), three surgery knees, shoulder repair, bilateral carpal tunnel and three surgery back. I'm six months post double spinal fusion. Anyway, you get the picture, they don't make bikes for me. I need light, low gearing and upright. The theory is that the 3 inch wide tires with 12 psi will act sort of like a suspension. I'm shooting for 25 pounds and gear inch in the high 13s. I'll be using a twin chainring SCRAM carbon crank to get acceptable speed with the low gearing. So that covers light and low gears for my decreped physical state. The problem I am working on is to get me upright as my spine and hips are stiff from the back surgeries. So I have a 70 & 120 mm 16º stems with riser bars and a lot of spacers. The picture shows the bike with the 120mm stem. The 70mm puts me more upright. I am a little concerned that the extreme height of the stem will cause too much strain on the carbon fork tube. Anyone have a thought on this. I am real upright as shown. I haven't cut the fork tube down yet.
20180315_130601.jpg
20180315_130601.jpg
 
Where it sits you should be fine. But if you’re concerned about it, possibly look into a stem with more rise. They’re out there.
I’ve seen some pretty cool solutions for getting a higher stem on a threadless set up. I’ll seek out some pics

Edit- this was the first stem that cam to mind—

https://velo-orange.com/collections/stems/products/cigne-stem
 
I would assume the steer tube can be run full length or the manuf. would of made it shorter. The other area of concern would be the top tube length on the frame. Did you size the bike as normal or did you go a size smaller to shorten the top tube? Alot has to do about the frame geometry.
 
What about a bar that comes back towards you? I love the Nitto Albatross I have on my USAAF bike. It allows an upright stance with a perfect hand position for me (my wrists have decided they will no longer tolerate flat bars).
 
cman said:
I would assume the steer tube can be run full length or the manuf. would of made it shorter. The other area of concern would be the top tube length on the frame. Did you size the bike as normal or did you go a size smaller to shorten the top tube? Alot has to do about the frame geometry.
Click to expand...
That was a question I agonized over for several months before getting this frame. I have ridden a lot of demo bikes and generally ride better on small frames but I have two medium and one small Specialized so I ride both. My body size is between small and medium frames. When the fork tube is left long the fork angle makes the stem closer to your body. I went for the 17 inch frame, but it has a long top tube. I might reverse the 70 mm stem.
 
The steerer on the fork is left long by the mfg so that it will fit as many frames as possible before being cut down. Typical spacing under the stem is about an inch. I wouldn’t go crazy with too many spacers.
 
Dizzle Problems said:
The steerer on the fork is left long by the mfg so that it will fit as many frames as possible before being cut down. Typical spacing under the stem is about an inch. I wouldn’t go crazy with too many spacers.
Click to expand...
I have 3 inchs of spacers in the picture and it gets me straight up. I'm hoping that I will be more flexible as the summer wears on and will be able to take out one spacer at a time. Thats the plan in my mind as I would like it to happen. I might be able to reverse my 70 mm stem and ditch a lot of spacers. I noticed that several racers in a local 100 mile mountain bike race had reversed their stems to get more upright and comfortable for the long haul. I have quite a bit of experimenting to do yet.
 
deorman said:
Just a thought.
https://www.niagaracycle.com/categories/wald-steel-handlebar-803-5-25-27-1-black
Click to expand...
I looked at similar bars at the LBS. They really felt I needed to go that way. For now I am going to disregard the stem height specs. I am more comfortable on my road bike with an extended fork tube than I was two weeks ago. Perhaps I can start out with a bunch of spacers for easy ridrs and slowly reduce the height by removing one spacer at a time.
Duchess said:
What about a bar that comes back towards you? I love the Nitto Albatross I have on my USAAF bike. It allows an upright stance with a perfect hand position for me (my wrists have decided they will no longer tolerate flat bars).
Click to expand...
I looked at similar bars yesterday at the LBS. They agreed and felt this is what I need. I haven't decided yet on this solution. I wasn't aware of all the options, I asked the right people, again.
 
Glad I could be of help. I wish I had learned about those bars from the beginning.

I also use the forward curve position sometimes as well.
 
Hey I work in a bike shop and have had a few customers looking to do the same thing.

One option is to go with an adjustable stem that pivots in the middle. This allows you to fine tune to get a the right position.

Swapping out the handlebars is always a good option and there are bars of all different heights. I'd look at the Jones H bar it comes in a riser version now and gives a few options for hand positioning.

You can also get a steerer tube extender that will clamp to your steerer and allows adjustment via spacers.
 
In response to this thread, I was thinking of a '180 degree' stem. After some searching...they have already been thought of, but, I can only find them for mini bmx.
crupi.jpg

You wouldn't happen to have any machinist buddies that could make you a riser version for your bar size, perhaps?

Jason
 

Latest posts

Back
Top