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Post by jacklively on Oct 31, 2020 11:09:22 GMT
Hi everyone. Amazing to find this forum. I’ve just bought a Viscount Aerospace (3rd gen fork) and plan to refurb it as a winter / gravel type of ride. It came with five speeds in the back on original wheels. They’re a bit shakey so I’ve found a set of wider rims to put 35mm tyres on. Now for the mech. The wheels come with an 8 speed cassette, so why not find 8 speed mech to go with it. I found someone willing to let go of some very nice old Ultegra 8 speed. Question is, will this all fit? I’m a bit of a noob so any suggestions welcome! Thanks and nice to be here. Jack  |
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Post by brianbutler on Oct 31, 2020 11:41:54 GMT
It will work. There are are a few considerations:
2. Check to make sure the wider tires will clear the frame.
3. The Viscount has 27-inch rims. If the replacements are 700C rims, you will need 4mm additional reach on the brakes. You might be able to lower the pads enough but you will have to check.
4. The derailleur will simply bolt on. The existing shifters will work and should have enough range to accommodate all 8 speeds, but it will still be friction shifting, not indexed. If you want indexed shifting, you will need to replace the shifters with ones that handle 8 speed indexed shifting for your specific brand of rear derailleur (most are interchangeable, though.)
This thread shows some rear derailleur options including a modern 7/8 speed inexpensive derailleur I fitted to my Viscount Sebring. I still use the friction down tube shifters:
Brian
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wheelson
Viscount
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Post by wheelson on Oct 31, 2020 12:21:28 GMT
Hi everyone. Amazing to find this forum. I’ve just bought a Viscount Aerospace (3rd gen fork) and plan to refurb it as a winter / gravel type of ride. It came with five speeds in the back on original wheels. They’re a bit shakey so I’ve found a set of wider rims to put 35mm tyres on. Now for the mech. The wheels come with an 8 speed cassette, so why not find 8 speed mech to go with it. I found someone willing to let go of some very nice old Ultegra 8 speed. Question is, will this all fit? I’m a bit of a noob so any suggestions welcome! Thanks and nice to be here. Jack Tire width at the chainstays/bottom bracket may be a problem. Hard to check that though without the wheel in hand and spreading the rear spacing. I just tried a 126mm 6 speed hub, 650B x 38’s in an Aerospace and it was pretty tight. Some good measuring might work but nothing beats trying the parts firsthand. Best, John “wheelson” |
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Post by oldroadietehachapi on Oct 31, 2020 15:17:34 GMT
I have several bikes having 8 speed and 126mm spacing. It can be a close fit depending upon the design of the dropouts and stays. On my Cannondale and an aluminum Trek (fat stays) the clearance is tight but nothing touches, except on actual rides. I have found evidence of slight chain rub probably as a result of chain slap. To remedy this, I simply added a small electrical tape rub strip that lasts a year or two. If they were steel frames I would add a 1mm washer between the jam and axle nuts (both sides)this would require a slightly larger spread to the stays.
Best of luck with your project
Jim
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wheelson
Viscount
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Post by wheelson on Nov 1, 2020 3:06:06 GMT
I have an '80something Specialized Allez, steel frame and fork. It's the Mark DiNucci designed, Taiwan built model and it rides really great. In my latest standardization effort, I have 3 bikes with 8spd cassettes, triple cranks. In order to make the 7spd into an 8, I found an Ultegra 8spd cassette hub to replace the original 7spd RSX (without spreading the rear spacing), installed an 8spd cassette (11-32) and 28-38-46 chainrings. Not optimal, especially the high gear, but a smooth running drive train using Shimano SPD "brifters", 2300's as I recall. This is a great road bike and definitely a hill climber. Max tire size is 700c x 29 in Panasonic Urban something-or-other. (it's in the back of my Jeep and it's 11pm or I'd double check).
Point is, there's a lot of things you can do to upgrade/modernize a bike if you take your time, do a lot of checking along the way, and are prepared to make some modifications/compromises as you go.
Best,
John "wheelson"
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wheelson
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Post by wheelson on Nov 1, 2020 15:09:26 GMT
Adding to my previous post, I was able to use the "correct" Shimano RSX (long cage) rear derailleur as well with the 8spd setup. Again, I stress with any upgrades, be prepared for modifications/compromises. Some older bikes do not give in to change easily. The Viscount Aerospace has a fairly narrow front triangle due to the fact that it was not intended for super wide tires. The "fastback" or "shot-in" tucked in seat stays tend to make for a more narrow upper rear triangle. At least that's my take.
Best,
John "wheelson"
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Post by jacklively on Nov 2, 2020 20:11:51 GMT
I seem to remember measuring the rear forks at 130mm. It’s in the shed now but i guess it will all become clear when I put the new wheels on. I got some wide rims, so we shall see.
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ks1u
Viscount
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Post by ks1u on Nov 4, 2020 0:38:17 GMT
As Brian mentioned, if you have 700c rims then you'l need to check a few things. The 35C tires may be OK, but if they are still 27inch wheels I doubt more than 32c tires will work. The only brakes I could get to work on my Aerospace GP with 700c wheels were expensive Paul Components center pulls. I'm sure there are cheaper ones out there, but it might take some trial and error. I'm glad you found this group. Their collective knowledge has helped be immensely.
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Post by grosh on Nov 4, 2020 12:22:25 GMT
I have an Aerospace Pro that is used as a "winter bike" - frame spread to 130mm and a rim with 10 speed cassette fitted. You need to be careful about the position of the rear wheel so that the chain does not catch on the chain stay (small sprocket 11t). Also fitted steel forks, a YST threadless BB, compact 50/34 chain set, 9 speed Deore RD, second hand 105 shifters and changed the brakes for some MAFAC centre pulls. Using 28c gravel tyres on 700c clincher rims and all works well. - I also have a second Aerospace Pro kept in very near original specification!
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