Can I fit a 9 speed cassette on old 5 speed cassette bike or other way to get much lower gear?

GervisLooper

Hi,

I have a British Eagle Reflex 15 which I have owned for 2 decades or so.

Been in the garage at my mum's for many of those years and I just got it out and took for a spin yesterday.

Any kind of hills than a gentle one were a real struggle though.

I have spent last night and this morning catching up on the jargon and general advancements in the area in the years since I paid attention to this stuff (probably the 90s!) and I see a lot has changed.

3 and even 2 chainrings are now out of vogue in favour of loads of sprockets on the back instead.

I am not really interested in any of that except I want a HUGE 'dinner plate' as I see the term is given, big cog on the back for hills.

Unfortunately I noticed the bigger ones seem only available for the larger speed of 9 and up. So would that frame take a 9?

I have seen a nice one with large 46 toother for a reasonable price at only £28 Shimano Cues CS-LG300 9 Speed Cassette, 11-46T at halfords.

I counted the current teeth on back and front and back it is:

14/28

with front:

28/38/50. I don't mind not having access to the top, biggest one, as hardly every used anyway.

Now I just looked up the bike name online and I saw one that sold for only £45 on ebay 2nd hand.

As the cassette would cost almost the price of the bike I am wondering if it is even worth pouring any kind of money into this one rather than buying another, more modern second hand one.

That was my initial thought however having looked at overall prices it seems most for similar priace are similar spec and age as my one then there is a big jump to 150+ for more modern looking offerings. Also looking at the cheapo frame only new ones they start at like 150 so it seems I might as well make this work somehow.

The crux of the matter will be based on what people reply as to whether that 9 speed cassette would fit on the 5 speed framed bike as I doubt they existed when that bike was made. I am wondering if the spacing for the frame pegs has to be wider now or if it is pretty much the same but the sprockets are just closer together?

I found a second hand 7 speed cassette on gumtree which is the shimano MF-TZ500-7 that, looking up the specs, appears to offer 34t for the largest cog. Second hand only a tenner. So less money and maybe would fit better on the frame but also less teeth to give less dramatic benefit.

I was gifted another old bike last year or so, since gave it away, which seemed to have a similar size cassette as that one. It was certainly better on hills than this one but it was still a struggle and not a comfortable in steeper climbs.

So I would be much more interested in getting that 46t or so as I could imagine that would really make the hills more pleasant.

Btw I don't mind a bodge job if I could somehow get it on the wheel but would not have access to all gears just as long as I could access that sweet "bailout out gear". I very rarely use higher gears anyway since if going at the speed or on flat they would be effective I will just coast.

So everything rests on what people will reply as to whether I could fit a 9 cassette on that frame or not, somehow, some way. I don't care a hoot about aesthetics and if I could modify it to fit in some way I would be all for it.

I know I will probably have to get a new chain, but I am wondering if a derailleur will also be required and anything else? If the required parts and corresponding price keep mounting I will have to consider if it is worth it but since the frame is fine and all the parts could be removed to another one someday I don't mind spending a bit. I don't mind hacking my way to success on this old frame given the large step to get a decent frame of a newer class and given I am satisfied with its performance other than wanting a considerably lower gear.

Any other solutions welcome. Maybe a smaller chainring or a single bigger sprocket on the back, which I saw there are some for sale but seemed restricted to just a couple of new cassette models. Any way to hack that? I don't mind a big jump if changing from the 5 speed up to a bigger one.

EDIT: Hmm as I think about it, in terms of compatibility, smaller chainring might be a better line of attack. If I am unable to find one small enough I could make one from a back cassette sprocket and drill to a couple of metal strips in an X to fasten to the original holes.

Nasqueron

At the very least, your shifters won't work to jump between 7 or 9 gears when they're designed for 5 and they may not have the range to go top to bottom even skipping steps. You will also most likely need a new derailleur too as a 14-28 won't be able to cope with a 46

I'd just keep it as a nice hobby bike for flat runs and keep it going but look at another bike if you want the range of a modern big setup. 1x is more for mountain bikes by the way, you tend to see 2x is the dominant one on road

Johnmcl7

Seven speed or below use a freewheel, eight speed and above uses a freehub so you wouldn't be able to fit a nine speed cassette to your freewheel.  I believe you can't change the freewheel for a freehub without changing the wheel.

There are triple cranksets that start at 22 teeth but I've no idea about compatibility with your bike, it's a very long time since I've seen five speed being mentioned.

Herzlos

You'd need to change just about everything to go for more speeds, so I wouldn't bother.

You could put a smaller set on the front: 28/38/50 is fairly high, you should be able to get something like a 20/22 on the smallest. That'd give you lower gearing without having to change anything else, but you'd potentially need specialist tools to get the chainrings off. Any local bike shop should be able to do it for you though.

But realistically if you were going to be spending any more money than that I'd just look at getting a more modern bike - the technology has come on dramatically in 20 years.