I've heard rumours (probably from people who want to sell me new bars) that the stock RFS bars can't be cut down. I'd really like to lose an inch each side, but hate to trash a good set of bars. Any thoughts?
I've checked all the controls and everything seems to fit ok. The problem as it was explained to me is not fit, but structural. Changing the factory end condition by cutting the bars even a small amount will make them overly flexible. I can't find anyone or anything to confirm this. Magura doesn't have any warning on their website, but I'd be interested if the packaging that comes with an aftermarket set of Magura's has any such warning.
Cutting bars is a fairly common practice, and I would think the manual would have a precautionary note about this if it was a concern (they seem to have warnings about everything else, by their account I should be dead now :D )
FWIW, this is second hand information from a parts counter guy at a local shop. I've generally gotten good advice there, but there's always a first time.
The reduced leverage/flex relationship makes sense, but that would apply in varying degrees to all bars. Do you know if the Magura bars are double walled? If they are, could they be referring to some type of joining of the two layers that occurs at the end of the bar? I'll take a look inside after I pull the grips off, but that's the only structural reason I can come up with for not cutting the bars. Otherwise, I'm breaking out the tubing cutter when my guards come in!
The Magura, PT's, and Renthal Fat Bar are all made by the same supplier with different labels and finishes is my understanding, and none of these three are twin-wall construction.
Renthal does make a Twin wall, but this is a different bar and is laminated as you point out.
I also agree that flex is a part of every bar, however keep in mind the PT's are "engineered" to provide a certain amount of controlled flex with the cross-barless design, something that sets them apart from welded steel crossbar and bolt-on aluminum crossbar offroad handlebars. Taking an inch off the flexible part, the 14 inches outside of the bar clamp, is over a 7% decrease in the length of the lever. I can see where that may have an impact on the flex.
All that said, if you want to whack an inch off them and all the parts will still fit, then go for it. The flex is probably a bunch of marketing BS anyway :confused: .
As far as the tubing cutter goes, I find a hack saw with a fine tooth blade to be easier for this operation. I broke two tubingh cutters before figuring this out. Just dress it with a file when you are done. If you are a plumber or have access to the big iron then great, but your average copper tubing cutter does not work too well.
The ONLY way to cut down Magura bars is to cut the amount desired to narrow them in the exact middle of the bars. The KTM dealer I bought my bike from (Neeleys) in SC does this all the time for riders/racers. My bars are done, and the job is so neat its impressive. He cuts the middle amount out, then welds a piece of pipe inside the bars, then welds the outside, then grinds/sands the weld off. It is the only way to narrow the Maguras because of the taper. I actually had to move my "magic button" to the left side to make it fit right. He has done this for many of the top KTM pro riders. E-mail me if you want his # to have this done. I could not be more pleased with the results!:) I do not know about other brands of bars, but on the inside of the Maguras, there is a "middle area" of sorts, that lends itself perfectly to this!
Trl Junkie speaks the truth -- the best way to shorten is from the center. However, I have had no problem shortening Magura's or Pro-Tapers on the end, using a pipe cutter for a good straight cut (but you must be patient). The guy who owned my 400 EXC before me had made the mistake of cutting the stock Magura's BEFORE he measured for controls clearance... and when I got it, the "button" was on the left! So I had to replace with Pro-Tapers (lucky I had an extra set in the garage). The PT's are only trimmed about 1/2-inch on each end, the fit is tight, and the barkbusters just barely fit, but all is well now. And btw, you can shorten from the center too much, too.