Last night I intended to upgrade my daughters bike from a 14-28 5 speed to a 13-28 7 speed. Swapped out the freewheels no problem. Adjusted the axle to get a little more length on the drive side and put a couple of spacers in to keep the small cog from rubbing. Everything looked good so I go to dial in the derailer, a Suntour VGT, nice and smooth 1-6 (or 2-7, whatever) but I could not get it get it to shift into to the large cog. The thumb levers are cheapies but they were not maxed out on their travel. It looked like the derailer was maxed out as the parts were the cable routes through the barrel adjuster and the tightnening bolt were pretty much in contact. I figure I can play with the spacers on the drive side to get the bare minimum of clearance for the small cog but I don't think that will be enough to bring the large cog in a littel closer.
Is the lateral range of the Suntour VGT just not enough to take on a 7 speed freewheel?
Anyways, I had her try it out this morning before she rode off to school, "Dad it's so much better, it's like buttah." She listens to me too much. She wasn't concerned she couldn't use the 28 cog, but it bugs me.
Any thoughts? If it wasn't long winded enough I can get some pics up tonight.
Noahscape, i'm glad to hear you got a similar setup to work, at least I know it is something i'm doing and not a limitation of the mech. I did not re-dish the wheel, it is a new wheel, purchased last summer and it doesn't look out of center with the 7 speed cluster so I don't think it was needed.
Neal, I couldn't push it further manually, it's about 1/2 way between the two large cogs. The derailer was maxed out, the one thingy was hitting the other cable bolt ******, wouldn't go no further.
I first tried with no spacers and the small cog rubbed on the dropout. Then I put a couple of spacers/washers in and bingo, spun like a champ. I'm guessing the spacers were about 4 mm. I'm suspecting I overdid it, I think I will try to fine tune the spacing to get it to where the small cog is just a gnat's ass off the DO.