Tubes and riser stem.

[The Path Racer]

I bought a riser stem for a recently purchased 90's MTB. I found the handlebar position low and too far over the front wheel. In other words I need more of a hybrid bike seating position. I did know of the issue before I bought the bike.
The fixed stem riser has arrived and after placing it into position it almost certainly places me in the position that I'm looking for. The issue is that the top fixing bolt is right at the top edge of the steerer tube. If I remove the bracket for the cantilever brake then things look a little better but the headset cap still doesn't reach into the tube, although the bolt does tighten.
The more experienced on here will have wiser thoughts than me. I do have the option of sending the riser stem back and perhaps trying another option.

[Brucey]

I would suggest extending the steerer tube eg using epoxy resin and bits of Al tube.

[slowster]

I *think* this will work, but check the internal diameter of the steerer.

https://www.chainreactioncycles.com/p/b ... m+-+25.4mm

Edit - It's designed for converting threaded steerers to ahead. If used with a threadless steerer, a clamp (plus spacers and a top cap) will need to be used on the steerer to pre-load and secure the bearing (then remove the top cap). I think there are (or were) a few products that served that function, e.g. to allow stem and bars to be removed for packing a bike for travel.

[yostumpy]

^^^ No the best solution. but

https://www.google.com/aclk?sa=l&ai=DCh ... ECE&adurl=


This will work. You will have to drill out the star nut with an 8mm drill bit, then insert the quill to the required height, removing spacers as you go. Tighten up the quill bolt, then slip on the stem with required spacers under,if any, and use top cap bolt to set headset tension.NB there are 2 sizes, 1" and 1 1/8", I assume yours is the latter. I have had one on mine, for maybe 3 years. I also have one on the tandem, with no spacers under the stem, this allows me to set it by raising it to touch the top cap, or release the clamp bolts, slide it right down and round 100 degrees, to allow fitting in the Volvo.

Having gone down this route, you can add upto 60mm in height to the steerer, BUT you may find now, that a less 'fugly' stem with a shallower angle may be more asthetically pleasing. I certainly would not glue a bit on the top.

[SimonCelsa]

The first image looks OK. The top cap is not supposed to go 'inside the tube' but sits on top of the stem (or spacer if fitted).

As long as the top cap tightens onto the stem to set preload all is well. Then tighten the stem bolts (I assume there are 2 of them, can't see the lower one).

Granted, the second image with the brake hanger fitted is not a good scenario.

Or am I missing something?

[rjb]

Fork column looks too short for the frame. Has someone swapped forks from a threaded steerer to an ahead fork which is too short in the fork column? Looks like a Raleigh M trax frame which may have had a threaded steerer originally.

[slowster]

I think yostumpy's suggestion is the one I would choose, because the adapter can be used to pre-load the bearing (unlike the adapter I suggested).

Fork column looks too short for the frame. Has someone swapped forks from a threaded steerer to an ahead fork which is too short in the fork column? Looks like a Raleigh M trax frame which may have had a threaded steerer originally.

Stem stack heights in the 1990s varied and were often lower than the current standard of ~40mm. Low stack stems are still available, but I doubt that any would also provide the rise that the OP is seeking.

[rjb]

Stem riser adaptors are also available but may need more steerer length than the current forks provide.

[The Path Racer]

The first image looks OK. The top cap is not supposed to go 'inside the tube' but sits on top of the stem (or spacer if fitted).

As long as the top cap tightens onto the stem to set preload all is well. Then tighten the stem bolts (I assume there are 2 of them, can't see the lower one).

Granted, the second image with the brake hanger fitted is not a good scenario.

Or am I missing something?

Thanks all for the input from everyone and the technical suggestions. Much appreciated.

It is a Raleigh M-trax, complete with a few titanium tubes. Everything in terms of the forks, steerer tube, handlebars is original. The stem connector between the steerer tube and handlebars is original. No doubt about that. It still has the M-Trax logo on it. When it's mounted on the steerer tube it sits virtually flush with the top of said steerer tube. It's 35 mm high with just one centrally placed bolt to tighten it all up, pretty much like a seat post bolt.. The top cap is plastic but the lower part of it fits inside the steerer tube, perhaps it helps a little in terms of any tube deformation. . . but then again perhaps not. I'm guessing.
The new stem/steerer connector is around 1 cm higher than the original hence why the steerer tube looks short. It has two fixing bolts, one towards the top that is perhaps dangerously? close to the end of the tube. The other bolt is on the other side and not visible in the picture. Obviously it's somewhat lower and safer in terms of fixing to the tube. The top cap is too short to fit inside the tube although the fixing bolt seems long enough.

[The Path Racer]

Stem riser adaptors are also available but may need more steerer length than the current forks provide.
51gGrNWsnCS._AC_UF894,1000_QL80_.jpg

I've come across those. If the bottom fixing section is too high it results in the same problem, that's if it is a problem in the first place. I'm mainly concerned with the upper bolt deforming the top of the steerer tube, largely because it coincides with the very end of the tube.It may be slightly above it.
It may not be a concern at all. I just don't know.

[Brucey]

using epoxy resin is quick/easy/cheap [they sell it in the pound shop] and sourcing the tube should be easy too. A rather easy job, I'd say.

[mattsccm]

Simply, the steering column is too short for that stem. It should be just below the top of the stem to allow the toecap not to touch it. Wisdom says that the top clamp bolt must bind on the steering column not fresh air.
You need a shallower stem or the gadgets above. Be aware that not all fork steering columns have parallel walls which can hinder quill type stems.

[cycle tramp]

..if you wait a bit 531Colin will echo Brucey's advice and will show you photos of the steering tube he lengthen by brazing...

...I'm kinda surprised more frame builderd don't offer this service

[SimonCelsa]

The new stem/steerer connector is around 1 cm higher than the original hence why the steerer tube looks short. It has two fixing bolts, one towards the top that is perhaps dangerously? close to the end of the tube. The other bolt is on the other side and not visible in the picture. Obviously it's somewhat lower and safer in terms of fixing to the tube. The top cap is too short to fit inside the tube although the fixing bolt seems long enough.

As long as the top stem securing bolt binds onto the top of the steerer tube then it should be OK. You have the lower one as well after all.The top cap is not really that important once the preload has been established and the stem tightened onto the steerer tube.

If you're worrried about the upper stem fixing bolt being close to the top of the steerer tube (& perhaps causing deformation) then maybe fitting another star fangled nut into the top of the tube would allay your fears. Knock the existing one down a bit first and fit a new one close to the top of the steerer tube. That should work and seems a pretty easy fix?

Failing that try and source a 'leaner' riser stem, System EX also do high rise ahead stems although I'm not sure about the relative dimensions. Some of the other options are a bit fugly!

[peetee]

I’m a bit suspicious of what’s going on here. I suspect that age of bike should have a threaded steerer/headset.