Can somone help a mechanical numpty - trigger shift
Can somone help a mechanical numpty - trigger shift
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Kell

Original Poster:

1,708 posts

237 months

Monday 7th September 2015
quotequote all
After my full-size folding commuter snapped, I bought a small wheeled bike for the commute.

Which means I now don't have anything to ride if I want to go out at weekends with my daughter.

I do have two old MTBs in the shed though and have started to get one back together.

The problem I'm having is the trigger shifts. They're on an Orange P7 from 2000 and are Shimano XT 9 speed and 3 speed.

Both of them, for some reason, are not giving the full range of gears.

The one for the front mech will only do one shift, so I can have bottom and middle rings or middle and top, but not all.

And the one for the rear is giving me about 4 gears out of nine.

I've taken them apart to replace the cables and the front one at least, will shift around and give me all three gears when I push it round by hand and it will drop all three gear using the shifter, it just doesn't want to engage when using the thumb lever.

If it was just one, I might have thought it was broken, but as it's both, I'm figuring it might be more likely it's something I'm doing. Or not doing.

Any ideas? Or just buy two more?

shouldbworking

4,801 posts

241 months

Monday 7th September 2015
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Are they giving you all the shifts when the cable is not attached to the derailleur? If so, it's probably your limit screws restricting the range of motion.

Kell

Original Poster:

1,708 posts

237 months

Monday 7th September 2015
quotequote all
shouldbworking said:
Are they giving you all the shifts when the cable is not attached to the derailleur? If so, it's probably your limit screws restricting the range of motion.
No. Even when they're not connected to anything they're still not shifting.

Welsh Pirate

215 posts

157 months

Monday 7th September 2015
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These can both be fixed quite easily with plenty of TF2/GT85! Basically there's a little ratchet hammer in each lever that re-engages after the first few clicks. When they haven't been used for a while, the ratchet seizes up, giving the symptoms that you describe.

Spray a load of TF2 or GT85 into the shifter and go up and down the gears. Keep on going up and down the gears. Eventually, the ratchet will de-seize and you will have full use of your gears again (this may take a while and you might need to leave it overnight)!

Good luck!

Zigster

1,993 posts

173 months

Monday 7th September 2015
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Just a bit sticky with age? I had a similar problem with the shifters on an old GT MTB. I took the caps off the shifters, gave them a good dousing in GT85 and they work just fine now.

deadtom

2,769 posts

194 months

Monday 7th September 2015
quotequote all
Welsh Pirate said:
These can both be fixed quite easily with plenty of TF2/GT85! Basically there's a little ratchet hammer in each lever that re-engages after the first few clicks. When they haven't been used for a while, the ratchet seizes up, giving the symptoms that you describe.

Spray a load of TF2 or GT85 into the shifter and go up and down the gears. Keep on going up and down the gears. Eventually, the ratchet will de-seize and you will have full use of your gears again (this may take a while and you might need to leave it overnight)!

Good luck!
this sounds about right

Kell

Original Poster:

1,708 posts

237 months

Monday 7th September 2015
quotequote all
Thanks for the tip.

I'll give it a go.

Kell

Original Poster:

1,708 posts

237 months

Sunday 13th September 2015
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Cheers both.

Took one apart and squirted some wd40 all over it.

That freed it right up and then I noticed a large plastic screw that you can use for this exact purpose so the second one was a lot quicker.

Both working perfectly now and with a little bit of fettling, all gears are indexing properly.