I have a 93 Specialized Hardrock Sport that came with Shimano Altus ST-3T15 trigger shifters. They are pretty far gone. I want to replace them with something similar that will work. I have seen some Shimano Altus SL-M310 trigger shifters that look like a later version of my old ones, but just looking at the pictures visually, there are differences. My question is will these newer ones work with the Shimano Altus C10 front and rear DR's? The DRs that are on there seem to be fine. This is a 21 speed bike. 7 Cogs in the rear cluster, three chain rings up front.

I know that this range of Shimano products are not their highest quality components, But I am fixing this up for my eleven year old grandson who gives it his best intentions, but his bike still spends a fair amount of time laying in the grass getting rained on. There isn't any reason to go the long dollar on this bike.

I got the bike, with two others several days ago. Driving by a yardsale. Saw three bikes. Two seventies vintage Sears "Free Spirit" ten speeds, and this Hardrock. Paid twenty-five bucks for the batch. They are all ride-able. This one could use some new shifters, though.

I know. I spelled Shimano wrong. Probably some other stuff too. When the flames start, you can skip this mistake. I already know that I am stupid too, so you can skip that one as well.