Suntour X-Press Front Shifter Tips

[MSYT]

Hey folks.

So... I have a set of Suntour X-Press shifters that came on a 91 Giant Stonebreaker... could be 92. You know the ones, super simple mechanisms that make the arms cross each other when shifting. The bike hadn't really been used much so the shifters were a little still. I sprayed in a little lube, as you do. The rear shifter works a treat but somehow the lube.... broke the front shifter?!

Before it was stiff but would hold in the middle ring. Now it's clean it snaps from one extreme to the other.

Super simple design. Much like a thumby - the indexing is done via a ball bearing moving in to slots. Only 2 slots though weirdly. The problem I'm encounting is the spring on the main body is overpowering everything and causing that missing of the middle ring. I've seen the instructions for these shifters and it says to adjsut tension via the nut and I have but it either is too loose or too tight and you have to fight to shift.

So... in an effort to save them. Does anyone have an tips on making them useable. Reducing the tension from the lower spring somehow or replacing the ball bearing?

The lower spring is a shit design tbh. It's meant to be held down by a washer that slots over a nut shape... great... but the pivot it's meant to hook on to on the other lever is higher so it forces the washer up and spring out of position.

Pics to follow.

 

[raidan73]

They were really terrible shifters. Best advice is to set fire to them and get some thumbies. Sorry, not helpful I know I hope you can figure it out and get them working though.

 

[wesmamyke]

I've pulled NOS examples out of the package that won't stay in gear. They are possibly the most finicky shifters ever created.

 

[MSYT]

I've pulled NOS examples out of the package that won't stay in gear. They are possibly the most finicky shifters ever created.

Well that’s always good to hear

 

[sick-lizard]

After trying to use BITD these shifters finally persuaded me to move to Shimano... They were awful.... yes jumping gears... at the worst times.. l would pick any other Suntour shifter over them...

 

[Gtpulse]

They’re like an Airfix model of a shifter. Best tip is ditch them for something else. I may still have some I took off a bike if you need a spare.

 

[Bike Hoarder]

Have you tried them 'on the bike'? IIRC they use the spring tension of the front mech to balance the spring in the shifter, or am I just half asleep.

 

[MSYT]

Have you tried them 'on the bike'? IIRC they use the spring tension of the front mech to balance the spring in the shifter, or am I just half asleep.

Oh geez don’t tell me that if that’s the simplest thing ever I’ve overlooked I’m giving up

 

[Vindiu]

I might be some months late to this one... the left X-Press needs to be balanced by the FD spring or it will tend to go to high gear. It's not really an indexed lever either but a "Power Control" one where the detentes are just to give a feel of the whereabouts of each of the chainrings, but they will just stay at any position you want to leave them just like a friction lever.

There are differnt versions, your appears to be a 1990 second tier model (SL-PP00-L). The XC-Pro/XC Comp/XCD model (SL-PP10-L)had a better mechanism and a steel lever covered in plastic just where you puch. All of them where improved in 1991 with the SL XP10-L and SL XL10-L whit betters bushings that make the friction mechanism easier to trim. The right shifters (SL XP 10-R7) had an improved indexing ratchet that would also keep the downshift lever at a shallower angle relative to the handlebars in top gear. The bodies of both where less bulbous and lighter.

 

[MSYT]

Good to know! Thanks! I probably could have used them all along then!