niswanger

Hey gang,

I'm in the process of restoring my high school MTN bike. It's an older mid-80's chromoly XL Montagna with a 6-speed Suntour freewheel, Suntour SC Sport 7000 rear der., Suntour XC Sport 7000 front der., and these crappy thumb shifters (only model info is a small sticker that says "For 5000, 7000, 9000 Derailleurs" where they both had to be installed on the handlebars in the upright position and the rear was SIS-Index (click) and the front one was friction (but I don't think that front der. needs only a friction shifter I think an indexed shifter would work too.

So help me find a suitable upgrade on the shifters. I'm assuming, from some research, is that I need at min. a speed index shifter (more is okay as the der. stop screw will keep from further shifts). My preference would be the rapid thumb/index models in a lot of recent MTN builds. For instance, there's a GF MTN (2000 model) with a 7sp groupo that has been stripped down to just the frame/fork/bars/shifters that I can buy on the cheap and cannibalize the shifters from the flip the rest, would they work? I'll attach a picture of that as well.

daniell

I would first measure the rear dropout space. Being that it had a freewheel, it may be 130MM. For a cassette to fit, you would need 135mm.

70sSanO

Here is your “option”. Your Suntour derailleurs won’t work with Shimano trigger shifters and there really isn’t a 6 speed Suntour index option other than thumb shifters.

You can replace your Suntour gearing with Shimano 7 speed... 7 speed freewheel, any 7-9 speed mtb derailleurs and 7 speed Shimano shifters. It is not easy to add more gears with a freewheel setup.

This will be the least expensive route as you will be able to keep your wheels and crank.

If a donor bike has the derailleurs, you’ll still need a freewheel and shifters. You can use a Sunrace, or other Shimano compatible freewheel, but Shimano is probably better.

John

niswanger

Oh boy...

My rear drop-out space (inside) is 126mm. I really want to keep the bike as original as possible. My Araya Dimple 26" wheels are completely rebuilt/bearings/axels/skewers/polished/new decals too. I'm in the process of polishing these SR Sakae Oval-Tech 3 chain-ring cranks as well. New BB coming today and the Origin-8 6061 T6 headset is loads better than the pitted old Tange headset. Really the entire bike is restorable to like new except for these thumb shifters...they are really worn and the clamps are nicked/pitted. So really I guess I'm off to trying to find some better quality Suntour 6 speed thumb shifters on ebay? Bummer, was hopping to upgrade the shifting performance whilst keeping everything stock. Hummm?

Bill Kapaun

Put the old parts in a box so you can look at them.
If you want to ride q decently performing bike, you'll need some newer stuff. Else, it's going to be a constant struggle.

Retro Grouch 

What is your objective?

Cost-wise, you are starting down an unpleasant journey.

Jeff Wills

I agree. Mid-80's mountain bikes with indexed Suntour drivetrains are a dead end. Unless you want to strip the bike and replace most of the drivetrain (as SanO said) find another bike to work on.

IMO the cool thing to do with the bike is replace the shifters with earlier friction shifters. They'll last a lot longer than any indexed system and they'll teach you how to shift like your grandpa did.

HTupolev

If you want to keep the rest of the existing drivetrain but don't want to be bound to Accushift, you could always just throw a friction shifter at it.

veganbikes

126 spacing is really going to limit your choices and like others have said it will take a lot of upgrading beyond just shifters. Suntour sadly is no more and 126 is freewheel spacing only (realistically, there are minor blips of cassettes but really hard to find something to fit that tiny space and isn't some old part already)

Honestly I am 100% pro friction shifting at the front unless it is electronic indexing at the front is meh at best especially on a triple.

You could try and find some NOS or NIB XC Pro stuff but it ain't cheap and ain't super easy to find. Friction shifters are easier to find brand new and would still keep it old school and you might find you like the shifting more. On a flat bar bike you have easier access to the shifters so a friction shifter is much easier to use then on the downtube and being able to fine tune your shifting while riding is pretty great.

70sSanO

I don’t see a problem. Anyone who had 6 speed Suntour or Shimano in the mid-80’s could just unthread the 6 speed freewheel and thread on a 7 speed freewheel on 126mm dropouts. Shimano even made 126mm 7 speed UG/HG freehubs in the 90’s. If you want something special find an NOS Sachs Aris freewheel. I’m running one on my flat bar bike with 7 speed STX shifters.

As I said, 7-9 speed Shimano MTB RD & FD, 7 speed Shimano compatible freewheel, and 7 speed shifters. 7 speed M310/M315 will work.

As a side note, with so many people going to 1x, good used FD’s are cheap. Generations from now won’t even know what it is.

John

niswanger

Well guys, there's no reason why this rebuild will be too burdensome because all the parts/components except for the lower end Suntour shifters are in great restorable shape, from the welgo bear traps (going to restore them too), Nitto mid rise cruiser chrome bars (mint condition, don't make chrome like that anymore), Araya 26" rims with new decals/bearings spin very true, and the SR Sakae 3X Oval-Tech (polished to mirror and coated with my ceramic wash, I've had bare polished AL stay mirror like for 2 years like this) I'm going to stick to my plan. I have found some Suntour Accushift shifters NOS that I will probably snag, BUT...

Could you possible find an example Shimano 7sp freewheel, RD, and shifters that would work for my setup? The verdict is not out for me to keep these Suntours.

Bill Kapaun

You're just looking for someone to agree with you.
Not me.
Ignore List.

niswanger

Possibly...I have found that A. Those shifters are not readily available and when they are it could set me back $80 (the only thing left to buy, outside of some engine enamel and auto primer which is my method if I chose not to power-coat and based off of two power coat estimates I'll probably go that route.. B. Possible retrofit of Shimano 7speed but haven't seen the proof yet. I love spending hours restoring stuff and sometimes having to scrape it...labor of love can have its heart broken sometimes. This is a mid-level late 80's that just so happen to be the bike I road in high school. I also have a 1997 Specialized Rockhopper Comp-FS which seeing just that one decade, tons of improvement. This is for nostalgic purposes and also the fun factor of riding a 1987 MTN and then hoping on a 1997 at anytime just for the fun of it.

dedhed

https://www.yellowjersey.org/Suntour21.pdf

70sSanO

Congrats! Few, if anyone, here has a 35 year old bike they had in high school in pristine condition. Go over to C&V and there are plenty of people trying to track down some bike they had, or wanted to have, when they were young.

My advice is not good. Primarily because I look at what things cost today and not the original value, or worse yet, thrift shop value. I have tons of parts and nearly all of them came off ebay. Some of them have been unbelievably good deals and some fall into the I can't believe I paid that much category.

You've lugged 30lbs of steel around for all these years and you have to decide If you just want to get it working, want to make it period correct, or invest more than it is worth. Invariably, I'm in the latter.

Personally, I'd go on ebay and look for some LX560 or 563 derailleurs in really good shape. If the bike was really precious to me, I'd go XT 730/732. Shifters are your issue as there were few really good 7 speed. I have not used the M310/315 but I hear they work well enough.

You'll probably be hard pressed to find the LX/XT 7 speed bowl shifters, and I never thought they were that good, and these days are way too expensive. I've used STX 7 speed and they are fine, but I'm not sure if they are any better than the current M310/315.

Just find a Shimano 7 speed hyperglide freewheel. Probably 13-28 or 14-28.

Get new cables and housing. I use Jagwire.

Or... find a donor bike, or go to a bike co-op and throw on whatever works and is cheap.

Have fun!

John

niswanger

John, thank you, I actually rode the bike on college campus after my 6 years in the military...I think it's a superb steel cruiser. Now that I have a better BB and headset (lighter allow) it might be a tad bit better. In fact if I order these Suntour SC 7000 Acushift shifters it might shift better than before? But could you help me with the most probably RD/FD and shifters if I found a Shimano 7 speed hyperglide freewheel? Any links for reference? So the most probably RD/FD are LX560 or 563 derailleurs? What about shifters, when do I need to look for in shifters for this? I'm begging to think my reconditioned (with new loose ball bearings btw) Suntour 6sp is the most desirable because A. It's original equipment. B. The most cost effective choice.

70sSanO

Well, since you have gone with Suntour Accushift thumb shifters you are somewhat locked in. They are both Friction only (left/front) and Fiction or Index (right/rear). Your only issue will be if your original Suntour rear derailleur is not index compatible. If it is, then just install and see how it works; with new cables/housing. If it doesn't you have wandered onto a path less traveled, and will need a Suntour Accushift rear derailleur. I'm not up on Suntour mtb hierarchy, but a 4050 should work. Of course, if you use all friction then you can run whatever you have or want to use.

For indexing, any standard spaced 6 speed freewheel should work. I'm not aware that Shimano ever made a 6 speed hyperglide freewheel, back in the early 90's, but I think they make them now. You can use a Suntour Accushift or 6 speed Shimano Uniglide freewheel (both are expensive) or any aftermarket 6 speed freewheel.

At this time, I wouldn't plan on converting to Shimano. The good thing is that Suntour thumb shifters are built like a tank and should hold up well.

John

masi61

What part of your SunTour drivetrain is worn out, just the shifters?

XC Pro thumb shifters for 7 speed are pretty common on eBay used, sometimes at low prices. You can run a 7 speed Accushift compatible 7 speed “AP”, 4 prong Winner or 4 prong Winner Pro with your current 6 speed SunTour 6-speed (Accushift) rear derailleur and the above mentioned XC Pro shifters. I would think the rear shifting should be really good and the set-up should fit your 126 mm frame.

Shifting for the front derailleur is friction so a variety of set-ups should run double or triple mountain/hybrid or road cranks fine.

Could you post a photo of your current shifters and your current rear derailleur/freewheel area?

niswanger

John and Masi, better yet I'll post a quick video. I also put images in my OP. In summary, all components are in perfect working condition and they will clean up and buff up very nice. The ONLY components I want to replace (with a better model too, just like a mid/upper group set) are the shifters. My current FD (friction) and RD (index) are a bit worn-to-weather and the metal chrome clasps are just a bit lack luster. Again, I've found some NOS XC Sport 7000 Accushift shifters (they have nice alloy clamps) with original Suntour cable housing locally for $60 so I think I'm just going to snag them:

70sSanO

Thanks for posting the video.

The XC Sport 7000 Accushift rear derailleur should be fine with the SC 7000 6 speed Accushift shifters.

Since I’m not a Suntour Accushift 6 vs 7 speed expert, I don’t know if Suntour had different actuating ratios between the two. I don’t think they did because they offered a 6/7 speed shifter selections on some shifters. But if the rear derailleur indexed to the old 6 speed shifters, there should be no problem.

$60 doesn’t seem like a bad price for NOS.

John

niswanger

Finished the rebuild, converted from Chromoly to Beskar Steel...rides like a dream!