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I have started a new job, cycling roughly 17 miles (or 27 km) each day into work. Previously, it was a very short ride (less than 2 km) into university. I have two bikes that are currently falling apart.

The first is an old Rayleigh Impulse (vintage), with six speeds in the back. This has a severely warped rear wheel, and really needs a new chain and gear cassette.

The second is a Giant Huron, internally geared 3-speed. This has a damaged frame: The rear wheel is prone to sliding forward in the dropout, and the bike shop told me that it is a bit warped.

I need a new bike, one suited for the commute, but money is a bit tight at the moment... I am wondering how difficult it would be to put the rear wheel, and the front gear onto the Rayleigh with the good frame.

Is this just a very stupid idea? What tools would I need for this? Is there any reason to suspect that the components (for example, the gear-shifter) would not be compatible? How long would a job like this take for a relative beginner? Are there any pitfalls to lookout for?

Thank you in advance!

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  • Do the wheels have the same diameter and the same dropout spacing (axle length)? I’d just drop it in and see if it fits. You’ll need some way to keep the chain under tension with the internal gear hub and the Giant’s chain might be the wrong length.
    – Michael
    Mar 23 at 14:25
  • I didn't know about dropout spacing! I know that both wheels are 700, but the Giant cycle is a bit wider... I assume that I would need a chain-breaker to resize the chain?
    – user109527
    Mar 23 at 14:41
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    If "a pre-owned bike made for longer commutes would be of comparable price" to the cost of the repairs to bash your two current bikes together, then it seems like getting the 3rd bike would be the way to go. It is (you say) more suitable for your new, longer commute and it's likely (though certainly not guaranteed) to require less maintenance in the coming months when cash is tight. Ongoing maintenance on an old car is often more expensive than payments on a newer car and the newer one is less likely to need maintenance - probably the same with your bikes.
    – FreeMan
    Mar 23 at 16:51
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    This is certainly possible (if the parts match up well enough). And it's something a novice bike mechanic could probably pull off. But it will require investing in some tools, and it assumes you have a brain that can figure out mechanical things. Mar 23 at 17:33
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    I know new bikes are crazy expensive, and for lots of hobbyists no bike under £/$500 is worthy of interest, but it should be pointed out that a perfectly good second hand bike can be as little as £/$50. A £70 second hand bike has lasted me 5 years now. I'm not winning any races, but it's cheaper than a bus pass, and I don't worry about where I lock it.
    – Clumsy cat
    Mar 24 at 10:37

2 Answers 2

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It is probably possible. It is the kind of thing where going through it as a beginner is likely going to take a long time and present some unexpected hurdles. It would be a good thing to do for someone who values self-reliance or learning about bikes or simply has a lot more time than money. If you do it I recommend enjoying the process and not worrying about how smoothly it goes or how long it takes. These sort of projects can easily go sour otherwise.

Googling around, the Raleigh Impulse appears to be a low-end 80s road bike. I couldn't find a 3-speed Giant Huron. Putting the wheel from it on to the Raleigh is almost certainly possible, but how complex of a job it would be depends on:

  • What sort of shifter you're going to be transplanting along with it
  • The spacing and chainline needs of the 3-speed hub in question
  • Whether the gearing range you wind up with if you just use one of the chainrings already present on the Raleigh would work, even if the chainline it's currently sitting at would also be functional. (Taking the cranks from the Giant along with the hub would likely work better and have you buying the least stuff overall, but is a much bigger hassle and would need you to have the tools to take the Raleigh's cranks and bottom bracket off and put the Giant's on).

The Raleigh is almost certainly 120mm or 126mm in back. If the Giant is a more modern aluminum 3-speed, it's probably 135mm and wants a chainline of around 45mm. That might be around where the large ring position of the Raleigh lands, or it might not be. Also if these numbers are accurate, you'll be spreading the frame on the Raleigh. This isn't that difficult or technical but can be intimidating. You can do it accurately with a piece of string and a ruler to measure things and a long length of wood to do the bending. For dropout alignment, if the old wheel's axle is straight, you can cut it in half to make a dropout alignment tool, securing the halves on to each dropout with the axle hardware and bending the dropouts around after doing your rear triangle spreading and alignment until the dropouts are also aligned.

The commute distance you're talking about is considerable and so unless you get lucky, it is not a good idea to just run with whatever gearing you happen to land on if you use re-use the Raleigh's cranks. You can make it be whatever you want by buying a new 3-speed cog along with a chain, which are both very cheap. A basic chain tool is also cheap. Just transplanting the entire drivetrain from the Giant probably makes the most sense, and you could probably even take the chain along with it because those sort of bikes have essentially the longest chainstays that exist. You would still need a tool to shorten the chain. I'm assuming from its vintage that the Raleigh has horizontal dropouts; if that's not true you would need a way of tensioning the chain, which could probably do with the rear derailleur.

For the shifter, none of the sort of shifters that come on modern 3-speed bikes like the Giant really swap on to to drop bars in any kind of neat or straightforward way. If you were to willing to buy an older kind with a steel band type clamp, that could work. Otherwise you can just do it with the shifter it has and rely on finesse and tricks to not ruin the hub. One approach is measure the cable pull from each position on the shifter you've got and make marks on the Raleigh's friction shifter at the corresponding cable pull positions. All you need for that is a marker and a ruler. As long as it's close you won't hurt anything. Some people do a similar thing by feel or muscle memory.

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Be careful before putting money into new parts on bikes in this condition, the risk is throwing good money after bad. If you go ahead, get a bike into as rideable state as possible before investing in things like chains, cassettes and cables. Once you are sure the project will be successful, spend the money. Most of us have a box (or shed) of new or near new bike bits from failed 'experiments' such as this. Those of us with more experience know that this is likely to happen - and go ahead anyway, tinkering with bikes is fun...

Tools required can be purchased relatively cheaply in kits. The kits are mostly (and just) OK for home mechanics working on well maintained bikes, but on such old bikes, may not be good enough quality to deal with seized up fasteners and such like. In my experience working on old bikes you really require workshop quality tools. However, if you plan on cycling for years, such a kit is a worth while investment and as long as you work it within its limitations, will do the job. Don't be a gorilla when holding a cheap spanner.

If you decide to go ahead, local bike coop is a greet place to start for advice and access to used parts. Recycle centers (rubbish transfer station metal recycling) are places you can often acquire serviceable parts for bicycles.

From a purely financial POV, it will almost certainly be better to look for a cheap, used bike.

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    +1 for the last line. A cheap but serviceable second hand bike is most likely to be cheaper, more reliable and in the end more enjoyable than a put together of two poor bikes. Just find the right donor for the bike you need.
    – Willeke
    Mar 24 at 17:12

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