dcdavys

Hi y'all, I've got a bike with Suntour 7 speed accushift freewheel and x-press shifters. I think I've got my head wrapped around what I would need to do to convert to Shimano shifters/derailleurs while staying with a freewheel set up, but I see a lot more freehub/cassettes on Craigslist in my area. I could use some info/feedback on the pros and cons of switching to a freehub, as well as help with my shopping list.


It seems like I would also need a new (to me) wheel to make this set up work on my bike. Anything else I'm missing/forgetting?

Would moving from a 7 speed to 9 speed be problematic? (My dropout spacing is 126 mm according to the internet--I haven't measured; it's a steel frame).


This is the ad that got me wondering, for reference: https://raleigh.craigslist.org/bop/d...598197360.html


Also, this is a somewhat hypothetical question, since there's really nothing wrong with the original components. It's just a project bike that I'm looking for projects for. I half joke that I'll finish this bike by the time my son is tall enough to use it -- he's 30" now

SurferRosa

If wanting to index Shimano 7-speed with a freewheel, I'd buy brand new, all-chrome 7-speed Sunrace from eBay, like this one:

https://www.ebay.com/itm/175249444991

They come in 13-25 and 13/14-28.

The all-chrome offerings are better quality (ime).

You may need to re-space the hub to fit the wider cluster. My 7-speeds are usually 1-2mm more than 126.

maddog34

first... 126mm... an old road, or old MTB, frame?... Leave it as a 7 speed. As to switching it to a freehub wheel and adding a newer MTB groupset to it,... yah, not going to recommend that choice... but it COULD happen, if you want to try. The first step would be getting the frame dropouts reset to 130mm.... the XTR Front Derailleur will probably not fit your old frame.... etc...

ps.. a 7 sp. Freehub will fit easily in the reset frame at 130mm as long as the O.L.D. of the hub axle is 130mm... a 8-9-10 Freehub MTB wheel will be 135mm... not an easy reset.... and there is more to resetting a frame than simply bending things apart... and proper alignment and angling is required... got a bike frame Gauge and a Dropout alignment gauge lying around? You'll need them. if you have a Road frame, most of the 700c or 27" wheels/hubs with freehub design will be 130mm...

Benefits of a Freehub wheel over a Freewheel wheel? The Bearing load is shifted to the outside several mm on the drive side which reduces leverage on the Axle, thereby reducing the chance of bending or breaking the axle under extreme loads..... the selection and quality of replacement parts is also increased with a Freehub.. and a freehub/cassette is a bit lighter too.

most Shimano Derailleurs/freewheels will work with most Suntour components... to a point. Suntour went under right about when 7 sp. freehubs and Index, Gear-by-gear shifting first showed up.. i have not personally seen ANY Suntour freehubs/cassettes.

second.. sell it once you get it working, or ride it for a while, THEN sell it

third... buy your son a nicer, newer, bike when he gets to riding height... but have him around as you make your project work... he will learn more than you can realize.

The XT/XTR Group is a good deal, looks to be in nice condition... but it won't be an easy conversion onto your old bike.

I recall handing wrenches to my dad when i was a toddler.. i could spot a 7/16" or 9/16" box-open before i could count. Flat or Phillips screwdrivers, the ratchet wrench, etc.The '53 Oldsmobile was a favorite "project" of his...he sold it and bought the "57 Olds Super Rocket 88 Hardtop with the bigger "98" engine, factory custom exhaust headers,and Tri-power carbs/manifold.. a Huge upgrade!
He mounted Curb Feelers first, then added an Aroogah Horn from a Model A Ford....

Kontact

MTB 26" wheels came in 126, 130 and 135. These days you are unlikely to find a freehub 130 26" wheels new, even though that's the appropriate width for an MTB of this era with a 68mm BB shell.

So if you want to do this right, buy an 8/9/10 speed road hub and build a 26" wheel. If you feel the rim is in good shape, build it with existing rim and spokes (they will often work fine with this sort of 3 cross wheel.

You could also buy a 26" 135 wheel, take some spacers out of the left side and cut/grind the axle down, then re-dish. Or you could cram the 135 into the frame and live with it.

You can have the frame spread or not. Both will work. (Aluminum can't be spread, though.)

Finally, there are 9 speed freewheels. You'll have to add spacers to the axle and re-dish. They are cheap, so maybe a decent stop-gap. Dimension and Sunrace brands are reputable enough. No jumping!

Bill Kapaun

From- https://www.sheldonbrown.com/cribsheet-spacing.html

7-speed Shimano HG
7-speed 5.0 mm 1.85 mm 3.15 mm 31.9 mm Shimano IG
7-speed 5.0 mm 2.35 mm 2.65 mm 32.4 mm Sachs
7-speed 5.0 mm 1.8 mm 3.2 mm 31.8 mm SRAM Freewheel
7-speed 5.0 mm 1.8 mm 3.2 mm 32.8 mm Sun Tour "Ultra"
Freewheel 7-speed 5.0 mm 1.85 mm 3.15 mm 32.4 mm Sun Tour
MicroDrive 7-speed 4.8/5.0 mm 2.0 mm 3 x 2.8 mm(L) 3 x 3.0 mm(H) 31.5 mm

ALL but the ST MicroDrive have 5.0mm spacing between cogs, so your shifters/RDER shouldn't be any wiser.
IF you "centered" the MicroDrive on cog 4?, your error (0.2mm = .008") shouldn't be "that much"

>7 speed freehubs have a longer body which doesn't work well with 126mm spacing.Uou have to remove 3-4mm from the NDS which has an undesirable effect on wheel dish. (NDS spokes don't have sufficient tension)
Using an Offset spoke bed rim can alleviate that, but you're talking about building a new wheel. I have a hunch that's beyond your desire?

A Shimano compatible FW should spin right on??

Kontact

Hey Bill, the OP is trying to convert the bike to 9 speed.

126 spacing is fine for 7 speed freewheels and 7 speed freehubs. All 7 speed road freehubs were 126 as were many 7 speed MTBs. The OP's bike is 126 7 speed already.

dcdavys

So my bike actually has 700c wheels. It’s a 1990’s hybrid. Does everything you said still hold true?

dcdavys

I was tracking until this line. I already have a 7 speed freewheel--are you saying that for newer 7 speeds (or alternate brands?) I may still need to re-space?

dcdavys

er...yes? It's a1990's hybrid--so a little of both

So if keeping it as a 7-speed freewheel, if I need to replace the freewheel and want to still have index shifting, I need to be on the lookout for index shifters, 7 speed RD, 7 speed freewheel, and chain. Is that right? Can I keep my FD/crankset and existing shifter, or would that just be goofy?

I'm crushed you don't think my son will think this 1992 Crisscross is as cool as I do I figure if he doesn't like it, I'll hand him my toolbag and he can build it into something different. When I was in middle school/high school I would have died to have a bike this snazzy. I was on a third-hand hand-me-down Huffy with a stuck seatpost that wasn't my height hah.

dcdavys

Interesting I haven't seen that proposed much when I was digging around the forum. The consensus seemed to be that Suntour accushift components wouldn't work properly with other freewheels unless I switch to friction shifting, which I don't particularly want to do. I guess as a first step, it wouldn't hurt to try...if it works, fine, if it doesn't, I still need to swap out some parts.

You're right, building a new wheel is beyond what I'm interested in doing! I'm surprised a 7 speed freehub wouldn't work with the existing frame, though, because the higher component bikes in the same line up as mine have the exact same frame, but came with a Shimano 7 speed Hyperglide cassette. Maybe the internet has misled me and the frame really does have 130mm spacing...

Kontact

Yes, except 700 130 wheels are easy to find. 130 7 speed was common for a few years on MTBs. My 95 MTB is 130 with 8 speed

I dont understand what you want for your other responses. 9 speed Shimano will not shift on any 7 speed cassette or freewheel. 7 speed anything will shift on a 7 speed Suntour index freewheel.

Are you trying to go 9 speed or 7?

dcdavys

I was under the impression that Suntour accushift shifters/DR are not compatible with other brands' freewheels, and since Suntour freewheels are pricey/hard to find, I am just on the casual lookout for decent used components that I could switch to when my 30 year-old freewheel bites the dust. I happened to see a 9 speed freehub set on Craigslist and wanted to know if I could make it work, but I'm not terribly invested in any particular speed or set up, I just mostly see freehubs on craigslist in my area and I mostly see Shimano brand.

I guess my question is/was 2 part--1) can I switch to a freehub with relative ease? (i.e., do I just need a new wheel plus the drivetrain parts); 2) can I switch to a different speed freewheel or cassette with relative ease?

The consensus seems to be I need to stick with 7 speed freewheel unless i respace my frame--although maybe I got that wrong or there's dissention....

Kontact

if you just want a fresh 7 speed freewheel, buy a Sunrace 7 snd it will work without any hub modification.

If you want to change speeds, then it depends what you want to do specifically, but then your Suntour shifter/derailleur is no longer usable. It only shifts 7.

Freehubs are an expensive mod unnecessary to what's being discussed. Respacing might also be unnecessary and depends what you're doing. Respacing is not necessarily a big deal. You'll have to pick a plan before you can receive one tidy answer, but my earlier post covers your options.

Bill Kapaun

That was >7. You know, greater than 7....

Kontact

You said 7 speed freehubs were longer in your post.

kunsunoke 

You can switch to a 9/10 speed freehub, but it will require a little bit of work on your part.

The rear hub will have to be swapped out for a Shimano or Shimano-compatible cassette type. If you are handy enough, you could swap out the hub yourself, or have a bike shop do it for you. It's probably a better option in the long run to get onto a cassette hub, as you run less of a risk of bending axles over time.

Shimano still makes 9-speed cassettes. HG400 series or better work just fine. Once you get a nine-speed cassette on your new cassette hub, it will be possible for you to use the XT/XTR shifters and mechs. An even better choice (IMO) would be using the XTR mechs, installing drop bars, and using SL-BS77 Dura-Ace bar end shifters with aero levers. You'd be turning the Criss Cross into a gravel monster.

The wider rear axle will be an issue in the old 126mm or 130mm drops, but you can actually stretch out the drops enough to get the hubs to fit - or just cold-set to the new spacing (130 or 135mm). The Criss Cross frame is Chrome-Molybdenum steel, so it should be okay to cold-set if you go that route.

Kontact

I don't think doing all that is going to fix his steel rim problem.

79pmooney

Re: 7-speed hubs - first, two choices. Freewheel (FW) and cassette. Dropouts must be set to 126 OLD or larger. Hubs must have axles at 126 length or long enough to match whatever larger OLD you decide to go with. (Steel frames can be reset to pretty much anything. Whether that is advisable is another matter entirely.)

Now, FW vs cassette? How much do you weigh and are you a bike beater? Us light, gentle types can ride 126 OLD freewheel hubs with their poor bearing spacing without issue. Others bend or break axles just looking at them. Replacement axle could be hard to find for popular hubs as most of the originals have been bent. There are fewer 126 cassette hubs and cassettes out there as that window was short before 8-speed and on took over but they are far stronger hubs.

If you are one who can ride without breaking axles and can find a FW 6 or 7-speed 126 OLD hub, I'm pretty sure you will be able to ride it a long time running SurRace FWs. But go to their website and see if you can live with their cog choices. They made some odd (to me) decisions.

Kontact

I have to say that this is absurd. Every derailleur bike on earth had a freewheel until the mid-80s. A ton of MTBs were produced with freewheel hubs well into the '90s. The vast majority of freewheel bikes didn't have any axle issues at all, and many of them are being ridden daily to this day.

dcdavys

Thanks, this is helpful, and I like your enthusiasm, although my real end goal for this bike is to go flatland bikecamping with my one year-old in a kiddie trailer -- I probably don't need a gravel monster for that and I think I'm probably also unlikely to bend an axle, but it never hurts to dream big

dcdavys

her steel rim problem

Hondo6

A large majority, yes. But every? Hardly.

Shimano introduce their first freehub rear hubs in the late 1970s. Other freehub designs predated Shimano's, but they weren't successful; Shimano's was.

I own two personally that predate 1981 1982. One has a date code of "DD" (April 1979), and the other has a date code of "FG" (Aug 1980 1981). Both appear to be 6-speed Uniglide and have approx 126mm OLD.

The older one ("DD" date code) is actually a "Schwinn-approved" part (I got it NOS, still in the Schwinn bag, last year). So while they weren't yet common they weren't exactly unknown in the early 1980s, either.

Freehub popularity increased with Shimano's successful introduction of Uniglide SIS. Hyperglide's late 1980s introduction provided the final impetus needed to make freehubs and cassettes a de facto standard for all but entry-level derailleur-equipped bikes in the 1990s.

Edited to correct boneheaded error in date code to year translation above (see strikethru text).

Kontact

Not only that, but if you really want to put me in my place you'd mention the Schwinns that had fixed cogs and a freewheeling chainrings so you could shift while coasting. Take that, stupid Kontact!


But the point remains that freewheel hubs don't all destroy their axles and were on 99.9% of such bikes for decades upon decades.

Hondo6

No argument there. Through 7-speed, the freewheel design is adequate, and is workable for many even above 7-speeds. But Shimano's freehub design is the proverbial "better mousetrap".

Just objecting to the use of "every" in your comment above vice "most" or even "the overwhelming majority". I'd have had zero objection with your use of either of those terms.

Hondo6

@dcdavys ; generally, I concur with Kontact's recommendations. If you like the bike as-is and it fits your needs, provided the rest of the drivetrain is sound replacing the existing freewheel with a modern SunRace freewheel (they have a good rep) may work quite well, at least for the short/mid-term. I've read accounts of people having had excellent results shifting SunRace freewheels using Suntour equipment in indexed mode. Because SunRace freewheels are Hyperglide "compatible", they have similar shift ramps shaped into their sprockets. Reputedly shifting is considerably improved.

I'll see if I can find some of the info I've seen previously on that combo here at BikeForums. If I can find it, I'll post a link here.

Can't give you personal insight as to how well that combo works. My schedule for the next few months means that my planned SunTour 7-speed Accushift build is going to be "back-burnered" for at least that long. But a 7-speed SunRace 13-24 or 13-25 is what I plan on using for the freewheel. I have both, but the RD I'm planning to use specifies 24T as max largest for indexed shifting and I haven't decided whether or not I want to "push the envelope" or not immediately.