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Approx. 3 weeks ago I found an abandoned frame (including handlebars, fork, brakes, pedals and shifting gears attached to it). I decided to use it to build a new bicycle since only recently I've decided to learn more about these things (even though I have been riding a bicycle since the age of 3 :D). A friend of mine gave me an old MTB 2 months ago for spare parts if I need any. I decided to use the wheels (including the freewheel hub on the rear wheel) since they seem to be in order especially after cleaning and oiling the bearings and axle, and diameter-wise they are a perfect fit - 26 inch (actually my initial intent on mounting the wheels on the frame was to see what wheels would fit on it).

The problem I'm facing is that according to a friend of mine the shifting mechanism is meant for at least 8-speed rear freewheel hub while the freewheel hub the wheel from the old MTB has only 6 cogs.

My first question is what the model of the shifting gears is? The only thing that I have found are the labels on the various components that are part of the whole gear thing and they seem to be all part of a Shimano Deore XT set. Sadly when I looked online I found out that there are like 10 or so versions of this set throughout the years since the initial release. The parts look relatively new so I would exclude all models that are older than let's say 2005-2006 (correct me if I'm wrong). Is it really meant for 8/9-speed?

My second question is if it's possible to change the freewheel hub with a 8/9-speed without a need for replacing the whole wheel itself? The question of course applies only if the answer to the first one is "Yes, this is not a 6- but a 8/9-speed freewheel hub". This is probably a dumb question but since I've just started learning I don't want to screw things up. IMHO it shouldn't be a problem for close values (like 6 vs 7 speed if such a thing exists) since (to my understanding) rear cogsets with lower number of cogs have a greater distance between adjacent cogs while cogsets with a higher number of cogs have a smaller distance between adjacent cogs which makes me believe that in terms of width cogsets are in general similar enough and I shouldn't be bothered when switching on freewheel hub with another. I have another freewheel hub with 7 cogs from my previous bicycle and based on the measurements I've made the width compared to a 6-speed cogset is very small.

Below are some photos of the gears I have. Cleaning is currently undergoing so don't mind the rust and dirt. :D

If you need more information/photos I can provide these.

UPDATE: After doing some testing and also after looking closely at the rear derailleur I found that it's a Shimano Deore XT RD-M760 which - according to multiple sites - supports 7,8 and up to 9 speeds. I actually have a 7-speed freewheel hub from my previous bicycle however I am considering buying a 8-speed one. The chain I bought is a KMC Z8S which has 116 links in total (I have cut it to fit my wrong 6-speed configuration but I have a spare master link plus the rest of the chain so I should be able to recover from this mess :D). The labelling on the casing says that it's meant for 18, 21 and 24 speed systems hence with the 3 speeds on the front I can use this chain with a 6, 7 and 8 speeds on the rear. However due to my gear I have to stick to either 7 (that is 3x7=21) or 8 (that is 3x8=24) speed freewheel hubs. Given that I have an indexed shifter (as pointed in the comments) and some research I did I should go for an 8-speed freewheel hub, right?

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    You have index shifters, so you need to match the number of speeds on the shifter to the number of cogs in the back. So, if you have 7 speed shifters, you need a 7 speed cassette/freewheel.
    – Batman
    Apr 19, 2016 at 14:54
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    That's why i said with it disconnected, take the cable loose from the rear derailleur, if it still doesn't move in either direction they are seized up. Are there any other model numbers on the shifters anywhere?
    – Nate W
    Apr 19, 2016 at 16:04
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    Ah, okay. Will do that. As for the model numbers - I was unable to find any. Probably scrubbed away. Btw I managed to shift my gears. I accidentally pressed the break downwards and discovered that that is actually how you shift up. LOL I have never used such a mechanism with two levers per bottom/rear gear. The lever underneath the break lever is actually for shifting down. I was pressing it and was wondering why I was unable to change gears. On both sides the indicators were L (low) hence I was at the lowest speed possible. XD
    – rbaleksandar
    Apr 19, 2016 at 16:33
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    Only the gear is XT (from 2004 considering the model). A bicycle without wheels, chain, seat, not locked up, sitting in the bush covered with rust and dirt for weeks placed right next to the entrance of my faculty at the university is the very definition of abandoned. It took me two weeks plus 3 middle-sized WD40s plus almost 3L of vinegar and 100-150g of baking soda to clean up just the rust enough to actually see what's underneath all that. Perhaps it was stolen but considering the location and the fact no one took it for God know how long period of time my concious is as clear as ever.
    – rbaleksandar
    Apr 21, 2016 at 22:14
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    A thought: finding an abandoned bicycle with 9 speed XT level components is a bit unusual. Most cyclists would pass it on to a friend or keep it as a second bike, as it represents a bit of an investment to buy. Might be worth checking to see if was stolen and the abondonde by the thief, unless you are very certain of the source.
    – zenbike
    May 11, 2016 at 12:19

1 Answer 1

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Despite what others have written, you DO NOT need to match the number of gears on the rear wheel (cassette) to the number of positions on the gear shifters, especially for older shifters. Many 5, 6 and 7 speed shifters have a "hidden" click, which can thus be used to control the derailleur into the extra position, but conversely, if you are using a 5, 6, 7 or 8 speed cassette with a 9 speed shifter, you will simply not use the 9th position on the shifter. So long as the end stops on the derailleur are adjusted correctly, so the chain does not fall off the largest or smallest sprocket on the cassette, everything else will be fine. Some have written very complicated forums and blogs about how Shimano, and others, have changed their design over the last few decades, and you MUST match the shifters to the derailleur to the cassette. All I can say is that I, like many many others, mix and match whenever we have a need to, and often use 8 or 9 speed shifters and derailleurs with 6, 7 or 8 speed cassettes, with absolutely no issues and perfect shifting.

I currently have a 9-speed cassette on a 1990s MTB with 7 speed shifters; when riding it near home (I live in a flat part of the country) I have it adjusted so I can use gears 3-9 (using positions 1-7 on the shifters) and simply 'forget' about the other two ratios. When I take it to the hilly parts of the UK I adjust the end stops and take up the slack in the cable so I am using ratios 1-7 on positions 1-7 on the shifters, and 'forget' about the smaller ratios. This way I have the best of both worlds, with just ten minutes of adjustment between the two, and can source from a much wider range of cassettes, as 8 and 9 speed are still being made by a number of manufacturers, whereas 5, 6 and 7 speed cassettes are not (AFAIK).

Regarding chains, there is some variation: Shimano make chains that are good for 5, 6 and 7 speed systems, and narrower chains for 8 and 9 speed systems (and later really narrow for 10 and 11 speed systems). However I use SRAM chains and they are compatible with 5-8 speed systems (?) or for 7-9 speed systems (?) suggesting there is some overlap. Having ridden for over 25 years, around 4000miles a year commuting, leisure and cyclocross, I use SRAM "7-9 speed" chains on all my bikes, whether they have 7, 8 or 9 speed cassettes, and have not had any problems to date.

As you have a bike with XT parts (which some consider to be the best MTB groupset available) you could do a lot worse than stick with an 8-speed system using XT and Dura Ace parts. I have a Dura Ace equipped road bike ("downgraded" from a 9-speed system for reliability on longer rides) and an XT/XTR equipped all-terrain bike (as I mention above, I do not live in a mountainous area, so it is used on gravel tracks, forestrty commission paths and urban cut-throughs overgrown with stinging nettles and broken glass!) also 8-speed which both give me the same range of gears as from a 9-speed system, but with, so far, 100% reliability after more than 10,000 miles of riding.

As regards "possession of stolen goods"; posting photos on a forum is not the best way to go! Even if you suggest that you "found" a bicycle or parts, I would not post photos online, as the original owner might take umbrage and want it back. That said, I "found" a bike over 20 years ago and took it to the police station; they kept it for three months and then let me have it back because the original owner did not come forward to claim it. I built it into a touring/winter training bike, and have covered about 50,000miles on it, so am happy that I will not be prosecuted, as the police followed procedure for lost/found property and passed it back to me. Legally I will never be the "owner", but in reality there is no way now for the original owner to prove my bike is their bike and claim it back...

As regards an "XT spec bike" rarely being abandoned; I would invite anyone to come and look around my town. It is not a "university" town/city, but we have a college and uni campus here, and every week I see £200 and £300 machines abandoned because of a buckled front wheel, broken chain or mangled derailleur. After a few weeks they are robbed of parts (lights, front wheel if not locked seperately, saddle if quick release, etc.) and then slowly they go rusty and are removed by the council for scrap. I would hope they would remove them after 3-4 weeks, before they go rusty, store them for the required 3 months, and then donate them to a local recycling charity so they can help those in need in this country or abroad, or else sold to a new buyer with the funds going to help charity. What this needs is a change in the law to allow "ownership" of anything abandoned for 90-days or more whatever and wherever it is on public land e.g. cars, bicycles, old furniture, etc. provided the police or local authority have seized the goods, checked the details and held them for the requisite period. We will reduce the amount of bicycles etc. going to landfill or scrap, and help charities and third world countries to become mobile in one go.

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  • Thanks. I already figured that out and I've been riding it for a couple of months now. I actually first went for 8-speed and adjusted things so they can fit. Now I've just bought a set of brand new XT Deore wheels(really nice wheels,costed approx. 170 EUR together) and went for a 9-speed cassette so now things fit like a glove.I got some really great advices and help from a bicycle shop/workshop owner nearby and he told me that I had to change my chain since the higher the speeds the narrower the chain and the closer the cogs. The new chain I previously bought for the 8-speed didn't quite fit.
    – rbaleksandar
    Aug 8, 2016 at 18:16

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