how do i fix a slipping banana seat handle bar

[banana seat Brian]

well not that long ago I re-painted a banana seat bike for my wife,,now the handle bars slip back and forth,,,is it the ridges on the handle bars or the stem,,
when I wa a kid I think I fixed it with taking a beer can and making 2 shims,,put them in and tighten the stim....what do i do

 

[Wildcat]

If it is the same stem the bars came with, it should tighten up. I would loosen them up, slide the bars out and clean the surfaces. See if the grooves have worn off from sliding back and forth. Then put a couple drops of oil on the threads of the tightening bolt and tighten them back up. Also check the tightening bolt's threads to see if there's any damage. Run the nut all the way through the threads to see if it binds.

Anytime I've tried tp add a shim or anything, it never worked for long, especially with the additional torque high bars put on it.

 

[Uncle Stretch]

Seems like I have found when they slip its the stem that is worn. I have a stem and no matter how tight you do the bolt the bars still slip. I took a file and put a few small grooves inside the stem and it helped.

 

[icyuod2]

you could always drill a 1/8" hole through the stem and bars and insert a small steel pin. (old dremel stem would probably work)

do it right, and nobody will even know its there.

 

[deorman]

Another possibility is that the gap where the bolt passes through is contacting too soon, because repeated torquing of the bolt has distorted the stem. Grinding or filing the inner surfaces could fix that. If the bolt is not threaded all the way to the head, it may be stretched, or too short due to the aforementioned distortion, replace or maybe add washers.

 

[ratina]

I took a set of small cruiser type bars from a Raleigh and tried them in a drop bar road bike stem, they wouldnt clamp tight, so I cut up a pepsi can and made a couple of shims, hasnt budged since I did it. Worked great

 

[spinman]

I added 25" apes to my '69 ray and they would always slip no matter how tight I clamped down. Tried shims and even a BMX style 3 piece stem. Still slipped. Finally just had the underside of the OEM stem welded to the handlebars.

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