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.