I have my older downhill race bike I built back in the day and I need help with the Shimano Airlines system. The main valve body leaks air due to the o rings being old. I know parts for these are either rare/super expensive or nonexistent. I've contacted Shimano for help, but everyone involved in this project has been long gone for years. Is there any company or person that has worked on these? I don't want to try taking something apart and break it. Please help!
by AZAKMS
3 Comments
There’s a vintage downhill mtb page on Facebook. Incredible resource. That’s your best bet at this point.
If you really want to go ahead and try to fix this, from my experience, your best option might be to buy a box of miscellaneous o rings and hope the right one will be in there. This was how I found a good swap for a pump ages ago I couldn’t find the ‘right’ o ring online for a few years ago.
good luck to you. don’t forget silicone based lube for use with the o rings to stop them drying out. at least that’s what I would do. some people disagree, all I know is, my pump still works.
https://www.ebay.com/itm/187366449351
personally I would take the airlines off and put something else that uses a cable on instead but if you really do want to try to fix this then that’s my best guess.
Orings are nearly always off the shelf, especially for something with such low production numbers. You can likely buy a metric oring assortment and find everything you need. Anything you can’t find, measure the inner and outer diameters, as well as thickness with a caliper and order accordingly.
These systems aren’t all that complicated. I suspect you may actually have a leak on the push fittings for the air lines, which usually just needs a new hose. Again, these are standard industrial items.
These docs may be useful for you:
* https://si.shimano.com/en/pdfs/si/5TX0A/SI-5TX0A-000-00-ENG.pdf
* https://si.shimano.com/en/pdfs/ev/SL-AR01_SM-AR01-1923/EV-SL-AR01_SM-AR01-1923A.pdf
* https://si.shimano.com/en/pdfs/ev/RD-AR01-1924/EV-RD-AR01-1924.pdf