SJX426 

126mm spacing. Is there room for any 7spd or do I need a Ultra 7? How about an 8spd?

https://i985.photobucket.com/albums/a...reewheel01.jpg

fucxms

If it's 126mm, then any ol' 7spd should fit. Never heard of an Ultra7, you might be thinking of Ultra6 (for 120mm spacing). 8spd freewheels are a bad idea because of axle bending/breaking issues. You'll need a new hub for an 8spd cassette.

SJX426 

I have an Ultra6 on a bike. They also made an Ultra7 for a short period of time. There are 8spd freewheels too.

TejanoTrackie 

You can still find Suntour Winner Ultra 7 freewheels on eBay. I have a Winner service board which allows me to build regular 5 and Ultra 6 freewheels for 120mm dropout spacing and regular 6 and Ultra 7 for 126mm dropout spacing. I don't think you can stuff an 8-speed regular screw-on freewheel on a hub spaced for 126mm dropouts, but there should be Shimano freehubs that will work. I have a Shimano 6-speed freehub with regular spacing that fits in 120mm dropouts.

T-Mar

Um, maybe. The question isn't just dropout spacing. A seven speed freewheel is slightly wider than a standard 6 speed, despite the narrower spacing. While you might have clearance with the dropout there may not be sufficient clearance with the stays. Frames meant for seven speed often have the inside of the stays flattened for extra clearance with the chain. You won't know until you try. Generally, if it doesn't work, a thin washer added to drive side of the axle will add sufficient clearance.

Jaeger

It should be no problem at all as long as you have friction shifting, which I assume you do.

I recently did exactly that and the 7-speed freewheel was only very slightly wider than the six-speed I took off. It didn't require fiddling with spacers or redishing the wheel or anything. Just a minor adjustment of the derailer limit screws.

Ex Pres 

Ultra7 = marketing hype for a standard 7s freewheel. Almost every 7s freewheel, except some Campy, are 5.0mm (Ultra) spacing.

oldpedalpusher

If you have a 126mm steel frame you can easily fit a 130 axled cassette hub with no frame modifications. That's what I did with a 1974 Raleigh 531DB touring frame when I upgraded from a 6 speed freewheel to slick shifting 8 speed cassette...


Simple friction shifters rendered the whole indexing issue moot...



Greg

TejanoTrackie 

A Suntour Winner narrow 7-speed freewheel is 1.3mm wider than a regular 6-speed in regards to the outermost sprocket position, which is not very much. I did not have any problems with my 126mm frame. It was more of a problem when I installed a narrow 6-speed in my 120mm frame, because the increase in width was 2.0mm and my outside sprocket was larger (14T), however, the chain still cleared the seatstay. Both frames do have some relief in the seatstays on the right side, so I guess that it could be a problem in a frame that did not.

SJX426 

I do have friction shifting. What is the recommended freewheel manufacturer? Interlocks look good but why are they 2.5x the cost?
https://www.universalcycles.com/shopp...?category=1665

mparker326

Since most modern bikes take cassettes and freewheels are only placed on new cheapo bikes, the production quality has gone down. Interlock (IRD) introduced an excellent freewheel designed for those of us who still want to buy quality freewheel. You could also look for NOS Suntour on ebay.

SJX426 

The Holy Shimano Freewheels have poor produciton quality? IRD is a better choice?

Sorry, I really missed the whole Shimano is the "best product" development years. I don't have a road bike with index shifting. Not too thrilled with my MTB and Shimano shifting. Must be the poor quality end of Shimano.

TejanoTrackie 

Or the OP could check here >>>>> https://sheldonbrown.com/harris/freewheels.html#7

John E

I have had mixed success cramming 7 speeds onto a 126mm axle. However, one should always be able to add a 2mm spacer to the right side, re-center the axle, and redish the wheel.

ricohman

Here is 7 speeds in 126mm. No problem.

SJX426 

I am fully aware of https://sheldonbrown.com/harris/freewheels.html#7 Thanks.
The reason I added the pic was for your assesment of available space. Harris prices are => Universal and about 3000 miles closer. I can order and pick up without shipment cost.

The other point I am interested in is the shifting quality between the two. I expect it to be better than stock with the modified teeth, even with friction shifting.

Jaeger

I almost bought an IRD freewheel but I found a Suntour 7 speed freewheel in new condition on E-bay.

In theory almost any new freewheel should shift better based on the new teeth designs, but the cheapest ones are likely less durable than these old Suntour freewheels. I can say my 7-speed Suntour 13-28 freewheel shifts just as well as the six speed 13-23 freewheel it replaced.

I've heard good reviews of the IRD freewheels and was prepared to buy one but in the end I didn't so I can't vouch for them personally.

Jaeger

It looks like it should fit, but we're talking about millimetres here. It's pretty hard to judge from a pic and you'll never really know for sure until it's on there.

SJX426 

Sooo.... I removed the freewheel and measured the axle diameter, 14.76mm. It is a Mavic 500 hub with there own axle. I don't know how it comes apart yet.

Anyway, there was some concern about going with an 8spd cassette due to bending axles. With a 14+mm axle, I would think the risk is smaller than with the typical 10mm.

Another interesting finding was that he pieces at the end of the axle, don't know what they are called, are Campagnolo parts. They are the pieces that have the serated edge that contacts the drop out. Mavic drilled out the treads. sliped them over their axle and retain them with c-clips. They are marked CAMP and 82. I assume 1982. The root of the threads are still visable after being drilled out.

SJX426 

So I measured a IRD 7speed freewheel and took a measurement below. Looks like it will fit. Does anyone know the overall axial length of an 8spd?

Road Fan

I had exactly this problem using a Shimano Megarange 7 speed on my Woodrup. I had to space out the wheel about 3 mm and adjust the wheel dish.

Road Fan

Should work on a 130 mm old hub. allowing 6 mm on each side (normally) extra length to fit in the dropouts normally, you need around 142 mm axle length.