martin18152

I'm rebuilding this bike, so far I have replaced the tires, seat, all cables, kick stand, shifters, break handles, and breaks.

I replaced the old break handles and shifters with a shimano combo break shift unit

I want to replace the front and rear derailleurs, not sure what to buy, front derailleur seems simple, clamp style, and tub dia. range, with number of gears, the rear, I'm not so sure about. My question is what is the difference between the mountain bike version and road bike version? I have a 3x7 gear set, seems similar to MB.

I seem to have some problems tuning up the rear shifter, it down ****s into higher gears easily, but likes to skip gears in up shifts into lower gears, is it possible that the new index shifter is not compatible to the rear cassette. To get in the gear I want, I shift past, the drop down.

I don't have a lot of experience rebuilding bikes, but I'm a Mechanical Engineer, and red a little, and watched a few Utubes.

Any help in picking the proper derailleurs is appreciated, or any other advice.

katsup

All 7 speed Shimano (3 or 7 speed) MTB or Road dérailleurs should work. My 520 is similar to your 750 and uses a bottom pull 28.6 clamp front dérailleur (M650). I can't guarantee your frame is the same clamp size, but look for Deore LX, DX or XT components. XTR is the highest, but the most expensive.

Which shifters did you add? Is the cable attachment point to the dérailleur correct? If both the shifters and cassette are 7 speed, it should be compatible.

Photos would be helpful.

Soody

https://www.sheldonbrown.com/derailer-adjustment.html
you might find this helpful

A new rear mech is probably not necessary, but if you really want one then RD-M310 is probably the one.

good luck dude

rseeker

Subscribing.

Needs more pictures please.

martin18152

thanks for your replies.

Tried to post a picture, it would not let me, said I had to have 10 posts first. I actually found a local shop that specializes in treks, the guy there assembled these bikes back in 95. He said that I had everything adjusted adequately, but some of the old Sntour derailleurs are not compatible with the new Shimano index shifters. I bought a Shimano Acera derailleur, should solve the problem. I still have to install it. I was also told that most all the clamp styles 3 speed derailleurs will work as long as tube size is right

Bianchigirll 

This bike?

Mogens

Check out the thread dedicated to 90s Multitracks in the Hybrid forum if you haven’t, lots of enthusiasm for them over there.

Korina

Participate in some forums, should get your post count up fairly quickly.

My '94 750 arrived in the mail last week. Out of the box it was a surprisingly comfy ride, barring the flat bars. Currently at the mechanic's, having the wheels trued, prior to stripping it for the powder coater.



Such a pretty paint job.

martin18152

Yea, my hands use to seriously go numb on those handle bars, lowered my seat , raised the bars , put on some hand grips with a wide hand rest , now they are tolerable

ramzilla

Shimano Deore RD-M591 is the best 7-8-9 speed deal around. Plenty available. Cheap. Easy peasy. I keep several in my spare parts kit for whatever. They fit almost everything.

ramzilla

Oh yeah. They must have made a million of these things. Damn fine stuff.................................

https://www.emkmall.com/products/rea...speed-mountain

due ruote 

That’s the bike you are sending to the PC? You have high standards.

Korina

Like I said, the closer you get the worse it looks. There are serious scrapes on the fork and top tube, through to the metal, and it looks like someone scratched their initials on the top tube then covered it (badly) with clear fingernail polish, with lots of other random abuse. The PC has a gorgeous grass green that'll look wonderful with a shiny clear coat.

Edit: Just to clarify, this isn't a resto (sorry guys), this is a make-it-look-gorgeous-and-ride-amazing project. Although I do plan to confuse people by putting period correct decals back on.