Lubing a twist-grip shifter
 

I acquired a Sun recumbent trike over the winter (to go along with my road and mt bike). It's a 21 speed, with grips that twist to shift. They are very stiff to shift. My wife is starting to ride it some, and she can hardly shift it. Do I need to lubricate the cable, or is there and adjustment somewhere that needs to be loosened? The bike has sat for a couple years without being ridden (was kept indoors).
If it just needs lubrication, what type lube should I use?

My guess is the cable, but it could also be in the derailer or shifter. Cables generally don't need much lube, so I'd recommend shooting everything full of WD40. If things are still stiff after that you must disconnect the cables and find the source of the friction by testing each piece independently. The cables/housing might need to be replaced, but I doubt it. WD40 works wonders on that stuff.

+1 on lubing the cables. Grip Shift (SRAM) shifters used to require a specific grease called Johnnisnot (really!), but I think that any light grease would work.

Silicone grease would be my first choice for the shifter internals. An auto-parts store will have it.

+1 Silicone won't damage the plastic shifter internals and I think "Jonnisnot" was a silicone based lube. Hardware stores also usually have silicone grease in the plumbing section.

I also agree on determining the source of the friction by checking each component separately.

There really isn`t much to the internals of a twist grip shifter besides a racheting mechanism so I doubt thats the issue. The cables on the other hand are always galvanized steel cables and unlined housing - both of which are prone to corrosion. Both zing and iron swell as they oxidize which will explain stiffness and eventual seized cables. Just replace the cables with stainless steel and use lined housings, grease or lube the whole assy and you`re good almost indefinately.

Before trying all the lubricating ideas mentioned above, check the derailleurs. Try moving them by hand to see how forceful the springs are. Try moving the derailleurs of other bikes for reference. If your wife's derailleurs have unusually strong springs, that may be the source of your problem. I don't have a fix for that. Anyone else? Change springs?

I switched front derailleurs recently. My old one shifted easily with twist shifters. The new one requires some muscle. I'm a rock climber, so I consider it part of my training. :)

If the bike didn't have good cables and housings then that could be part of the issue. And as mentioned directly above if the rear derailleur has a strong spring or if it's corroded at the pivots it will reflect back to the shifter as being very stiff to move.

If you disconnect the cable at the rear derailleur you should be able to test all three parts of the system separately and find which ones are the culprits.

The grip shift mechanisms are pretty simple but if they are dirty that won't help either. But to clean them you need to remove the grips. Once that's done you can just twist and pull on the twisting part and it pops right out. Take note of the cable routing and remove any covers if your version uses them. Once cleaned you can lube it with either some silicone grease as mentioned or even just any water resistant boat trailer grease. In particular be sure the little spring (the one that looks like SRAM's logo) gets a good dollop of grease.

As for the cable and housing if it's an older bike it's possible that the cable is corroded. It's also possible that it was used enough in the past that the cable has cut a groove into the inner lining of the housing. Frankly cables and housings on bikes should be replaced rather than fuss around trying to clean and lube them. You can do all that only to find out that the cable has cut a groove in the lining and that all your fussing about was for naught since it'll still pinch in the groove and be stiff to move. Bite the bullet and get some new index shifter housing and buy the better quality "Slik" or equivalent smooth die drawn cable which will tend to not cut into the lining as much as the regular cables. The feel they provide on the shifter will likely make you want to change out the brakes to the same sort of cables. Yep, they really do feel that much nicer.

first off DO NOT USE WD40. This stuff is basically a solvent. My guess is that the shifter problem is caused by cables and/or housing. I would start there and while you are replacing the cables lube the inside of the shifter with a little johneysnot.

Are the shifters labeled "Sunrace" 7-speed?

The primary ingredient in WD40 is a lightweight mineral oil and its primary use is as a lubricant and as an anticorrosion treatment. It might work as a solvent simply because of its low viscosity - but thats pretty expensive solvent. There are other products that do a better job for a lot less money.

Likwise - there are more suitable products on the market for cable lube, but if WD40 is all you`ve got - I`d have no issues using it.

I concur with Burton.

WD40 is largely a solvent but it also contains a light oil which, as it happens is just about the best option for lubing cables and housings on a bicycle as you're likely to find. Granted it'll take the better part of a month or more for the solvent part to evaporate but when it does you're left with a light oil which is pretty much all you want in a bicycle cable housing.

The issue is that the plastic itself is more than slippery enough on its own. By the time WD40 or any other lube helps it's an indication that the cable has cut a furrow into the housing's liner and that the housing itself needs to be replaced. Using some lube, such as WD40, is just a stop gap solution at this point to buy some time until new housings can be installed. Even better would be new housings and that die drawn smooth surface "Slik" cable option to put into the new housings.

On a few models, yes. On many others, the twisting part is retained in one fashion or another, and brute-forcing it will break the retention device. If in doubt, post some photos of the one in question. SRAM in particular seems to take fiendish delight in making as many different types as they can think of :crash:

This site has Grip Shift Lube (limited supply).

https://www.cleverconcepts.net/finis....com/index.php