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Frozen old Shimano 100GS

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Frozen old Shimano 100GS

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Old 07-13-19, 04:44 PM
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Mickey2
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Frozen old Shimano 100GS

This is a bike that's been in storage for more than 20 years. The bike has all original parts, including break pads and there's no signs of wear on the side of the rims. There's no sign of rust at all, it's a bit dusty and had some dried up dirt and grime on chain. It been taken for a ride or two, but hardly more than that. The rear fender is missing and seem to be the only thing needing replacement.


The main issue seems to be the shifters, they don't work properly. It's the old type shifter where you geared up on one lever, and released the gear on a second lever just below. I have looked up 100GS on the web, but couldn't find the exact model of shifter. It's not the type you sort of feel you way to each gear, it should click in place relatively precise. Is this a common problem? I have applied spray can oil to all openings I could find, and will let it seep over night. I have so far been a bit hesitant to take the shifter appart, but I may have to. Is it straight for ward, with out any particular risk? Should I start looking for different shifters, or did they work? They are hardly worn, but can of course be damaged. It's just a hand me down bike I aim to keep at the cottage or as a back up.


I found this old tread, but I couldnt' make much of it than oil, oil and oil.

Last edited by Mickey2; 07-13-19 at 04:47 PM.
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Old 07-13-19, 06:52 PM
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The shifters are most likely showing the lube's age, it's becoming gummy and causing the ratchet pawls to not freely engage and release with the lever's movements. Short term fix is to flood the shifter "pod" with spray oil like WD40. Long term is to remove the pod from the rest of the control assembly (including any thin plastic seals) and soak min solvent, air blast clean and relube with same air blasting and increasingly thicker lubes.

BTW the same age is degrading all the grease in the bearings... Andy
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Old 07-14-19, 04:42 PM
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Thanks Andrew. I had the cap off the shifters and freed the moving parts in there manually with with my finger and poking around with a screw driver. You were right, it was gummed up grease, and it took a bit of effort to get it all unstuck A pawl spring on the rear derailleur shifter was out of position, and that's probably why the bike had been put aside decades ago. It's shifting fine now, but I shall keep up the frequent oil application for a few days.
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Old 07-14-19, 06:45 PM
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Thanks for the follow up. These shifters can go for years with once a year lubing. Andy
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