the_don

This is my Klein Quantum Pro. I have had it a year and want to change to a modern short drop and reach handle bar.



Also, I find a little bit too stretched on it (it's a 57cm frame and I usually ride a 56cm) so I want to change the stem to a 90mm from the current 100mm.

I did a lot of searching and heard that Klein did make a shim to fit 1 1/8th stems, but finding one after so long is proving impossible. I also saw that Reset Racing started making a shim. But after 2 months of emails, I have had no response.

So I did some calculations and figured I need to go from 1 1/16" = 26.9875mm to 1 1/8" = 28.575mm.

A difference of 1.5875mm so the shim will need to be 0.79375mm or 0.8mm.

I found this Cane Creek seat post shim that goes from 27.2 to 28.6mm, which is a diameter change of 1.4mm or 0.7mm shim thickness. As it is so close to the correct dimensions, it should slip on snugly and mate the 1 1/8th inch stem nicely to the Klein steerer. Hopefully the 0.1mm will be fine when the stem is tightened. I am planning to trim it down to size as it is surely too long.



I also bought the new stem, a nice 3T Arx Pro that I have been seeing a lot of on the weight weenies forum. It is lightweight, looks nice and is pretty cheap, but comes in the size I want, 90mm with -17degree angle to have a parallel stem like I currently have.



Finally, I bought some new bars, I would love to have gone for the 3T Carbon Ergonova, but budgets are tight at the moment, so i opted for a Deda RHM02 at 1/10th the cost, which have nearly identical shape and nicely flattened ergo tops at just 50g added weight. Also seem much stiffer than my current 25.6mm bars which should be named, sir flex-a-lot.



And to top it all off, a cheap carbon top cap with 1 inch star nut.



I am planning to pick up replacement carbon spacers once I have completed the operation, as I am not a fan of the chunky plastic spacers the MC2 has. I can give or auction away the unwanted old MC2 parts as I hear there is demand for them.

I have nearly everything I need for this little project accept for one vital thing. The MC2 tool. Luckily, one is flying to Tokyo from New York at this very moment. I posted on the Klein owners group in Facebook and someone is being kind enough to lend it to me. Shipping came to $5.60!!!

I will document the process to help future owners escape the evil that is the MC2 stem. It's a great design, but since it is no longer produced, when having to change the stem, it's a great proprietary problem.

the_don

And why doesn't the Title of the thread match the title in the forum list!?!!

Steve530

Looks like that shim will work, but I would measure the parts if I were doing that. 16 gauge sheet steel might also work.

I have two Klein bikes, but neither has the Mission Control stems. When I replaced the BB bearings on the 1983 Performance frame, I couldn't find anyone who had the Klein BB service tool, so I had to improvise. It's great that you could find the appropriate tool.

I have Deda Zero100 handlebars on my 2006 Q-Pro. They work well for me, so I think you'll like the RHM02 handlebars.

Keep us updated on the project.

DiabloScott

You don't really need the star nut, right? You have the Klein headset with the steerer bonded to the bearings? So you just need a cover?

Interesting find with the seat post shim, I'm looking forward to your results.

Steve530

I guess an expander nut might work better.

the_don

Yeah, but expanders are more heavy and expansive. This just has to sit in the tube to allow for the top cap to be held on. the 1 inch seem to be the best fit for it also.

I guess I could just superglue the top cap in place.

Kimmo

Nice find - the missing link!

...What's the deal with the special tool for the MC2 stem?

BTW, IIRC this Aheadset-style setup predates their actual appearance on road bikes by a few years, doesn't it? Klein used to be pretty cutting edge stuff.

the_don

the_don

So the tool arrived in the post! Thanks Mark from New York for lending it to me!



Step 1, Remove the MC2 stem.

This was pretty easy, put tool on and turn anti-clockwise. The silver top part spins, but is connected to the stem itself.



When the stem is taken off, the collet will still be on the steerer tube, it was greasy, so I used a tissue when pulling it off.



Now the Klein Spacers can be removed. Exposing the entire tube.




Step 2, Make the shim.

Again, a simple task, I put the shim over the steerer and used some tape to mark where i want to cut.



I then used a crappy hack saw and got a surprisingly straight cut. I then filed the bur off and removed any imperfections with the file also.



Pretty nice fit.



Step 3, Put the shim and new stem on.

Yawn... This is too easy, but the juicy fun part. As the Klein doesn't use a top cap to put pressure on the head set bearings, I can put the stem where I want on the stem and not use any spacers (but I will get some later).


Shim could do with 0.2mm more thickness I think, but it's on very solid, so I guess it is within tolerance.

the_don

Step 4, Prehensile Top cap install.

This is really just to stop water getting into the steerer and look nice. I was thinking of an expander plug, but star nuts are so cheap. I got 1 inch and 1 1/8th inch star nuts and checked which works better. The 1 inch one looks the best fit, so pop it in and hammer away!





I then measured the amount of empty un-spacered steerer and bought some carbon 1 1/8th spacers to fit, with a flared one at the bottom.

igknighted

Looks great, nice work!

Out of curiosity, if the Klein headset doesn't use pressure from the top cap to hold it together, what does?

DiabloScott

Glue.

Kimmo

Nice work, looks slick!

Wow, that's pretty trick.

the_don

Went for a ride on it this morning. The new bars are so nice, and finally my position feels perfect! I actually feel comfortable in the drops now too!

So now it's time for a gratuitous large photo of the complete bike.

Kimmo

Pure horn aside from the dork disk, but I guess you're allowed to have it cause of the Spinergys ; )

You know what would be awesomely cool with those? 60mm front hub and custom fork.

Steve530

Nice work.

the_don

Yeah the dork disc... The wheels are in mint condition and look brand new. So I wanted to leave it on for posterities sake. But it also looks a bit dorky, but then again if the chain ever does throw (I have never had it happen ever) then it should protect it...

As you can see I go through the arguments in my head every time I look at it.

Kimmo

Like I said in the dork disk thread, it's understandable they're fitted to Spinergys.

Imagine the expensive carnage that would ensue in the event of a mishap... you can't just replace a few spokes.

Mind you, I'd be tempted to run em without one, cause of the minimal chances of said mishap and the enhanced total badass factor of a DD-less Rev-X.

the_don

When I got the wheels, I started to take it off, it's just held on with thick sticky pads.

But then I thought that it could save me someday and helps it look brand new even though the wheelset are like 10 years old.

Since then, I haven't needed to have the wheel off and I really can't be bothered to do it just to remove the disc.

TheRedMantra

Are you interested in getting rid of the mc2 stem and collet?

southern rider

Ok how about a photography lesson too? So your Klein is a 96, my Quantum II was still using the quill stem and 1" head tube. Does that sound right, even similar years?

DiabloScott

The collett thing was Quantum Pro model only... not Quantum or Quantum Race or Quantum II or Q-Pro or Stage or any other model.

My History of Klein Road Bikes page

the_don

Hey! That's a pretty decent photo for an iPhone. Not professional quality, and the composition is crap and the background too busy and a bit too much HDR effect on it...

But Like Diablo Scott said, the quantum2 came with a quill stem in '96.

the_don

I could certainly be monetarily persuaded to part with it...

southern rider

Actually DiabloScott, your history of Klein Road Bikes and links to specs was real handy when I rebuilt my Klein, stripping off the hodgepodge nonconforming group. The chainline specs helped me upgrade from 8 speed and the bike shifts like a dream now.