70s Motobecane Grand Touring

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onyxaxe

onyxaxe

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I bough this bike for 125 on Craigslist. It's my first road bike and it's been a journey lol. My question is. is there any reason I can't just attach a new 6 speed freewheel on the new wheelset I bought?. The hub is threaded for a freewheel cassette. I can't get the %^&* cassette off the old wheel. My current derailleurs will handle 28T, I want to use the Shimano Tourney.

Blacked out

 
If the new wheelset is english-threaded for a multi-speed freewheel, then you can put a 6speed freewheel on there if the wheel is spaced at 126mm.... or if you have a suntour Ultra 6 freewheel, but those are getting scarcer as time marches on. If the wheel is spaced at 120mm, you'll want to add 6mm of spacers on the drive-side behind the jamnut, or just run a 5 speed freewheel.

If the frame is spaced at 120mm (prolly is if it's a 70s Moby GT), then you'll likely want to cold-set the frame to 126mm to accept the 6speed freewheel OR just run a 5 speed.

For real, having that one extra cog, imo, is not worth respacing frames at all, and hardly worth respacing hubs. At 126, you can go 7speed, which is slightly more worthwhile.... slightly.

If your new wheel has a cassette hub, then you'll need to run a cassette. You'll also wanna measure the O.L.D. and see what you're working with....

Now, you're messing with a French bike, so beware of oddball threads EVERYwhere, esoteric BB shells, and even spooky things like a helicomatic rear hub on the orginal wheelset. Motobecane was way more "normal" than Peugeot, so you might be OK. And, if that's an 80s frame, it's likely to be made in Asia, with more standard threads and a 126mm rear-end.

I hope this helps.
 
Bicycle808 said:
If the new wheelset is english-threaded for a multi-speed freewheel, then you can put a 6speed freewheel on there if the wheel is spaced at 126mm.... or if you have a suntour Ultra 6 freewheel, but those are getting scarcer as time marches on. If the wheel is spaced at 120mm, you'll want to add 6mm of spacers on the drive-side behind the jamnut, or just run a 5 speed freewheel.

If the frame is spaced at 120mm (prolly is if it's a 70s Moby GT), then you'll likely want to cold-set the frame to 126mm to accept the 6speed freewheel OR just run a 5 speed.

For real, having that one extra cog, imo, is not worth respacing frames at all, and hardly worth respacing hubs. At 126, you can go 7speed, which is slightly more worthwhile.... slightly.

If your new wheel has a cassette hub, then you'll need to run a cassette. You'll also wanna measure the O.L.D. and see what you're working with....

Now, you're messing with a French bike, so beware of oddball threads EVERYwhere, esoteric BB shells, and even spooky things like a helicomatic rear hub on the orginal wheelset. Motobecane was way more "normal" than Peugeot, so you might be OK. And, if that's an 80s frame, it's likely to be made in Asia, with more standard threads and a 126mm rear-end.

I hope this helps.
Click to expand...

Thanks for the taking the time to post that. The rear wheel I bought is 126, but it fit so the previous owner must have spaced it already. The rear wheel was 700c and the front 27 when I bought it. I think it's a 72'-75' based on the champange with black stripes paint job it had. I ordered the tourney, and the hub is freewheel threaded. We'll see if I messed up when my package gets here lol. Thanks for your help :)
 
To get the old cassette off, I would take it to my LBS. Looks like a fun project!
 
Package came this week. I threaded the new tourney freewheel onto the wheelset and all looks good. The moment of truth will come when I set up the gears.
 
Just realized that my shiftera are friction only. The tourney I bought doesn't fair well unless indexed I've read. I'll either take my old wheel to the lbs and have them remove the freewheel or I'll buy a new friction one.
 
It'll be fine. The ramps, theoretically, could lead to ghost-shifting, but I've gone friction with similarly ramped FWs and it's been awesome.
 
Yeah, I use a Suntour friction shifter on my daily bike with a modern LX rear derailleur and SRAM 8sp cassette, no issues.
 
The amazon reviewers were complaining about issues. If you guys had success I'll give it a shot. Thanks!
 
Oh, and if it's a Maillard freewheel with a large splined tool interface, your LBS should have the remover for it. Hopefully it's not a Helicomatic. If it is, hand it to a Francophile and walk away.


Sent from my iPhone using Tapatalk
 
Deathbike said:
Oh, and if it's a Maillard freewheel with a large splined tool interface, your LBS should have the remover for it. Hopefully it's not a Helicomatic. If it is, hand it to a Francophile and walk away.


Sent from my iPhone using Tapatalk
Click to expand...

Lol. I think it's just a basic Sunrace freewheel, thanks for the advice.
 
From the pic, it looks like it has cast dropouts- that's an indication of a decent quality bike. The bottom bracket probably is French threaded so if it's rough, try some new ball bearings first. That's a tall guy's frame, too, maybe a 62CM or so.
 
I think it's awesome that folks are repeating stuff i'd posted on this thread back in December. It makes me feel so... influential. :rockout:
 
I forgot to come back and post when I got it done. I've been riding it for about a month now. The only problem I've had is the chain jumping off the inner ring. My community bike shop tweaked it to where it's rubbing in the front derailleur while crossgearing. Meanwhile I'm learning not to crossgear :). I will post a pic that does it justice asap.

I had a hard time looking this bike up and still didn't find the exact model in any of the vintage catalogs (velobase and forums). Here are some specs that may be helpful. Note the original paint job was champagne with two black stripes on the back. It said Gran Touring on the toptube. No tubing sticker.

Toptube c-c 590mm
Seattube c-t 640mm
170mm SR custom 52-42 cranks with 119mm b.c.d
630 with 27 1 1/8 tires at 90 p.s.i. 126mm rear spacing
Fork has 50mm of rake

Surprisingly I have no problem riding this huge frame. I can standover it fine at red lights and such and emergency stops have been fine. I'm a 5'10" chick with long arms and legs.

I left most of it stock. I've also read that the tubing is Vitus 888. If I do anything else to it maybe a conversion. Regardless I need to stiffen it up, it's bouncy lol. For about 300 bucks total project (I had no spare parts or anything) I'm happy with it.
 
Took it on it's longest ride yet yesterday. Here it is:

fm743n.jpg
 

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