5 Speed to 7 speed freewheel conversion

Davebo777
Davebo777 Posts: 44
edited September 2017 in Workshop
I have an old Raleigh Carlton with 5 speed freewheel. I am hoping to convert it (on the same hub) to a 7 speed. I know I need to cold set the frame and align the dropouts but do I need to add any spacers either side of the axle ?

Thanks in advaance, DBo.

Comments

  • cycleclinic
    cycleclinic Posts: 6,865
    5 speed bikes are 120mm spaced. The may need some respacing it depends on the hub. Personally i would not respace. Getting the rear triangle aligned is possible but not that easy. Get it wrong and the wheel wont sit centered. Whats wrong with 5 speed anyway.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • 5 speed bikes are 120mm spaced. The may need some respacing it depends on the hub. Personally i would not respace. Getting the rear triangle aligned is possible but not that easy. Get it wrong and the wheel wont sit centered. Whats wrong with 5 speed anyway.
    Yes it is 120mm (119.9mm to be exact). The new 7spd freewheel is quite a bit wider so I think 130mm would be needed but I want to stay as authentic as I can. Nothing wrong with 5sp but where I live I need to get a 28 sprocket to go with my 42T (smallest) chainring. Can't seem to find a 38T or a 36T for love nor money in the BCD. The Huret rear derailleur will take a 28T sprocket so to get a smooth transition from 13T to 28T I want 7spd.
  • rolf_f
    rolf_f Posts: 16,015
    I got a 9 speed cassette to fit my 6 speed Raleigh Randonneur frame without any respacing by having the axle shortened. The wheel then needs redishing and ends up a bit weaker than before as the drive side spokes end up a little steeper.

    Don't know if that would work in this case but possibly worth investigating.

    Or I'd just get a crankset with a smaller inner ring. Cold setting is the work of the devil.
    Faster than a tent.......
  • Rolf F wrote:
    Or I'd just get a crankset with a smaller inner ring. Cold setting is the work of the devil.

    Thanks for the info. At some point I will get some new wheels as the rims are quite pitted. The hubs are fine though so I am happy to keep them for now. Just want to be able to manage our lovely Yorkshire hills and my ancient *& modern) knees don't like 42:24 as the lowest gear.

    Trouble with finding a smaller chainring is it's an old SR crankset with a BCD of 118mm. If anyone has one with less than 42 teeth I'd be happy to buy it and make life far easier.
  • davidof
    davidof Posts: 3,042
    I got a 28T six speed, which should go straight on. My shimano crankset also took a 38T small ring giving me an almost compact 38/28. Good enough for a day of 220km over 4000m on dirt roads in Chiantishire last autumn.
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  • Monty Dog
    Monty Dog Posts: 20,614
    7 speed will fit on a 126mm OLN frame which is what we had between 120mm and 130mm - the freewheel will probably be too long for a 120mm hub, but spare axles are easy to come by and your wheel will probably need re-dishing
    Make mine an Italian, with Campagnolo on the side..
  • There are 5 speeed 14-28T freewheels readily available so this is the obvious cheap and easy solution.

    There might be rings avilable for the old SR chainset. drop me a pm and I will open a catalogue tomorrow and see what goodies are available.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • As luck would have it, buying fever took over and I managed to find a QR 130mm/95mm alloy wheelset (from Parkers of Bolton - no connection).

    That seemed far more logical than faffing about with re-dishing a perfectly good set of original rims.

    Filed down the front dropouts to accept the wider QR axle. Perfect fit. Wheel almost spot on and runs nicely after minimal truing.

    Checked the frame alignment prior to cold setting and it was spot on. Dropouts were straight too.

    Used the RJ the Bikeguy method of winding out a threaded bar and it took to about 160mm to get a 130mm gap. Re-aligned the dropouts (again using RJ the Bikeguy home made tools) and the wheel went straight in.

    Re-assembled the rear derailleur into the 28T slot and set the hi/lo stops and Bob's yer uncle.

    Very pleased with the result. A big improvement for not much cash and it looks good too and stays with the character of the bike.

    Just need a 38T 118 BCD chain ring to seal the deal. WiIl PM you thanks CycleClinic.IMG_2062.JPG?dl=0
    IMG_2068.JPG?dl=0