Larger Chain Wheel & BB

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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

Sorry to keep harking on but I have just been looking at getting a Shimano front mech but then I realised that I would then need new levers. But it then got worse when I realised that given the chain set and xt rear mech that are fitted on the bike they to would need to be changed.
I have to say you would think this bike had been built in someone's shed rather than by a professional bicycle builder.
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CREPELLO
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Re: Larger Chain Wheel & BB

Post by CREPELLO »

What's wrong with the Campag front mech? I thought it shifted ok :? . Granted, they can be a little tricky to set up well, but there's no real need to go replacing all those other parts.
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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

CREPELLO Yes it is shifting ok but after all the advice I have been offered I thought it might be wiser to go all Shimano but as you read that would be more difficult than I thought it would be.
After fitting the 48t gearing and changing the chain rings from the Deore onto the XT cranks as its 175mm Cranks I found that the chain was getting stuck between the middle and small chain rings I scratched my head had a cup of tea and with music from Radio 2 ( unbelievably Vanessa Phelps is tolerable early in the morning ) in the back ground I decided as advised by Colin to lower the front mech and bingo it solved the problem. So as you know it only needs to be millimetres out to cause a problem.
Its only since I have raised the issue on here and received some great advice that I realised that my touring bike is more of a mountain bike and to be honest its miffed me as although I asked for a bike to allow me to climb over mountains when it was built I wanted it to have all road equipment which you can easily obtain from SPA et al.
Even obtaining replacement Deore XT 48 - 36 -26 chain rings is proving to be a nightmare and at least I have managed to order a 36t from someone in Italy.

Yet another hard lesson learnt then.
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CREPELLO
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Re: Larger Chain Wheel & BB

Post by CREPELLO »

Hondated, don't be too hard on yourself, nor your bike, although I know you feel it was created in a mis-directed way. Therein seems to be largely the problem. But it is a tourer AND a good one at that. Remember that a tourer is effectively a hybrid, borrowing from road and MTB components.

If you want more replacement chainrings, Rose is an excellent place to look http://www.rosebikes.co.uk/products/bik ... gs/mtbatb/ I seem to be able to get free p+p for some reason (which makes purchases even cheaper); you may be able to as well, although I haven't heard of anyone else getting this :?
Spa also sell non Shimano replacements for the XT BCD spacings.

I'm glad that dropping the mech a few mm has helped. Fickle things, front mech's.
Brucey
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Re: Larger Chain Wheel & BB

Post by Brucey »

I've been mulling over this and it seems to me that there may have been some confusion over the spec of the OP's bike from the start. It is fair to point out that every bike is a compromise of some kind and that unless you are clear about exactly where compromises are to be made, they may end up being made for you in some way that no-one could predict might not suit you down the line.

'Touring bike' is a somewhat ill-defined thing; for some folk it implies clearance for 40mm tyres, the lowest possible gears, and long chainstays etc for load lugging. For others it might mean 'anything that isn't quite a racing bike'. So when you buy a custom made touring bike you do need to have a very careful conversation with the builder; his 'default setting' may be one thing and you may want (or need) something different to that.

In particular the OP's bike has fairly short chainstays (for a load-lugging tourer). This immediately places a constraint around the maximum tyre size, the chainline (on a triple especially), the chainring sizes and/or the way the chainstays are made.

In a nutshell, unless you have specified this feature from the start, you cannot expect to be able to fit larger chainrings (on a triple especially) without running into problems on a custom made frame; a mass-produced one will often have a severely manipulated RH chainstay to allow some choice of gearing but this inevitably weakens the stay and/or necessitates that it is made heavier. If you are perfectly happy with that then maybe a custom-made frame is not the right thing for you.

I've only ever had a few frames built for me and I have had to be absolutely explicit about what I wanted wherever it differed in any way from the builder's 'default setting' to the extent that it has been put in writing, on a dwg, in black and white so there cannot be any confusion about it. And there have sometimes been cock-ups and I have been very glad of that dwg. But what I wouldn't ever expect to be able to do would be to change my mind about how the bike was equipped in some way (that no-one could predict) and then have it all miraculously work OK anyway.

So what to do now? Well the reason I'd prefer something different to the OP's original gearing is that when tapping along unladen I'd be wanting to use 44/17 (or similar ratio .. 34/13 anyone... :roll: ) quite a lot and that would leave me a choice of two badly-cross-chained gears for that gear ratio. One way out of this is to use a triple chainset with a larger set of rings so that this gear ratio is accessible using (say) 39/15 on the middle ring. But that would likely necessitate that the frame was built with this kind of chainset in mind in the first place.

So where the OP is now I'd be thinking that an alpine double setup might be favourite; 46/28 chainrings using a 12-34 cassette (or something) can be set up to give a nice chainline on the gears you might use most and other easily accessible gears with enough low ratios for most kinds of unladen work. I would bet money that you could reduce the Q value by about 30mm if you wanted to, too. Unfortunately this probably means shelling out on a middleburn chainset or something but you might be able to at least try out the ratios (approximately) by re-jigging one of the triples you have at present.

hth

cheers
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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

Brucey wrote:I've been mulling over this and it seems to me that there may have been some confusion over the spec of the OP's bike from the start. It is fair to point out that every bike is a compromise of some kind and that unless you are clear about exactly where compromises are to be made, they may end up being made for you in some way that no-one could predict might not suit you down the line.

'Touring bike' is a somewhat ill-defined thing; for some folk it implies clearance for 40mm tyres, the lowest possible gears, and long chainstays etc for load lugging. For others it might mean 'anything that isn't quite a racing bike'. So when you buy a custom made touring bike you do need to have a very careful conversation with the builder; his 'default setting' may be one thing and you may want (or need) something different to that.

In particular the OP's bike has fairly short chainstays (for a load-lugging tourer). This immediately places a constraint around the maximum tyre size, the chainline (on a triple especially), the chainring sizes and/or the way the chainstays are made.

In a nutshell, unless you have specified this feature from the start, you cannot expect to be able to fit larger chainrings (on a triple especially) without running into problems on a custom made frame; a mass-produced one will often have a severely manipulated RH chainstay to allow some choice of gearing but this inevitably weakens the stay and/or necessitates that it is made heavier. If you are perfectly happy with that then maybe a custom-made frame is not the right thing for you.

I've only ever had a few frames built for me and I have had to be absolutely explicit about what I wanted wherever it differed in any way from the builder's 'default setting' to the extent that it has been put in writing, on a dwg, in black and white so there cannot be any confusion about it. And there have sometimes been cock-ups and I have been very glad of that dwg. But what I wouldn't ever expect to be able to do would be to change my mind about how the bike was equipped in some way (that no-one could predict) and then have it all miraculously work OK anyway.

So what to do now? Well the reason I'd prefer something different to the OP's original gearing is that when tapping along unladen I'd be wanting to use 44/17 (or similar ratio .. 34/13 anyone... :roll: ) quite a lot and that would leave me a choice of two badly-cross-chained gears for that gear ratio. One way out of this is to use a triple chainset with a larger set of rings so that this gear ratio is accessible using (say) 39/15 on the middle ring. But that would likely necessitate that the frame was built with this kind of chainset in mind in the first place.

So where the OP is now I'd be thinking that an alpine double setup might be favourite; 46/28 chainrings using a 12-34 cassette (or something) can be set up to give a nice chainline on the gears you might use most and other easily accessible gears with enough low ratios for most kinds of unladen work. I would bet money that you could reduce the Q value by about 30mm if you wanted to, too. Unfortunately this probably means shelling out on a middleburn chainset or something but you might be able to at least try out the ratios (approximately) by re-jigging one of the triples you have at present.

hth

cheers


Well I hardly feel qualified to respond to that Brucey, thanks for taking the time to explain your opinion.

I suppose I can start by saying that at my initial interview to ordering the bike I did specify that I wanted to be able to climb mountain roads with it but I did not specify that I wanted to go off road in the Himalayas so why was mountain bike components used. After all I have cycled up many mountains on a racing bike.

I particularly like your point about agreeing drawings etc and if I was to ever have another bike made for me I would certainly do that. Mind you its something I would never do again as I agree with I believe something, you and others have stated before there are very few of us, that cannot adapt a shop brought bike to meet our needs anyway.

In particular the OP's bike has fairly short chainstays (for a load-lugging tourer). This immediately places a constraint around the maximum tyre size, the chainline (on a triple especially), the chainring sizes and/or the way the chainstays are made.


Wow I would never have realised that.

Given everything I have written about the bike on this thread and others if you want my honest opinion I feel that the bike was made at the cheapest cost to achieve the upmost profit and I put far to much trust in the opinion of the builder. At £2500 six to seven years ago it was not cheap.

A little anecdote to illustrate that point. A cycling friend of mine recently told me that he had discovered that a brother of the bike builder who are both sons of the original frame builder is now building frames and bikes in his own name in Bexhill. And this brother after their father died was the actual frame builder until for whatever reasons he left the company long before I brought my bike. So !
Brucey
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Re: Larger Chain Wheel & BB

Post by Brucey »

well obviously no one can know exactly what conversation you had with your framebuilder when you ordered your frameset/bike. But as soon as you say you want small chainrings and a triple chainset you are instantly in the realms of confining your choice to one of just a few chainsets that exist and of those not every bike builder will stock all of those. Most of them in those rings sizes will be 'MTB' cranksets, not 'road' ones. If you hadn't specified any particular preference then in the absence of some special clairvoyant skill how would anyone know which you might prefer?

Ordering a custom made bike is very much like getting a suit made. Most people don't bother and make do without. If you do have one made and it falls apart or the colour runs out of it in the rain then it is clearly not good quality. But if you turn round when the thing has been done (to your agreed specifications) and you say the lapel width is too wide, you've changed your mind about the colour, you've conveniently forgotten that you were told that it isn't machine washable, the number of pockets etc is now 'wrong', you've put on five pounds and it doesn't fit now and anyway it was a bit expensive, wasn't it...? -then really those are things you should have thought about before your ordered the bloody thing. No sense in getting worked up about it now, surely...?

No bike is going to be all things to all men but I think you have a really nice bike there and so would 99/100 other cyclists. People buy bikes like that because they want a quality frame that fits them, fitted with the bits they have discussed and agreed with the builder, not because they think they are 'a bargain' or whatever. Your cycling preferences will inevitably change as time goes on; if you are lucky you will be able to fit different bits to your nice frame and continue to have a machine the suits you. If you can't then that is just bad luck for the most part; I don't think there is anyone to blame per se...

cheers
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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

[quote="Brucey"]well obviously no one can know exactly what conversation you had with your framebuilder when you ordered your frameset/bike. But as soon as you say you want small chainrings and a triple chainset you are instantly in the realms of confining your choice to one of just a few chainsets that exist and of those not every bike builder will stock all of those. Most of them in those rings sizes will be 'MTB' cranksets, not 'road' ones. If you hadn't specified any particular preference then in the absence of some special clairvoyant skill how would anyone know which you might prefer?

This conversation will really have to end soon but for now you are missing my point. My point is that whether its a bike builder or in your example a tailor I have gone to them because of the skills and advice they can offer at a price, given I wanted a touring bike there are more than enough bikes out there with road gearing to take you around the world so why resort to mountain bike gearing.

-then really those are things you should have thought about before your ordered the bloody thing. No sense in getting worked up about it now, surely...?

You really do yourself a disservice by resorting to this kind of comment as I am not getting worked up about it but rather just openly discussing my opinions of it and perhaps at the same time trying to influence others that may be thinking of having a bike built considering their decision before spending out a lot of money.

I don't think there is anyone to blame per se...

That's correct there are two people to blame the person who built it and me for buying it.

If only I had read Robert Penns book " Its all about the bike " who funnily enough also rode around the world on a Roberts but then chose to buy a custom made Brian Rourke, before buying my bike.

One final comment I cannot help but think having read many of your threads and comments and the vast knowledge you appear to have that you in reality you are a bit more than a " cyclist " and possibly a professional bike builder yourself and that is why you seem to get a little touchy when their abilities are questioned on the forum.
Brucey
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Re: Larger Chain Wheel & BB

Post by Brucey »

hondated wrote: given I wanted a touring bike there are more than enough bikes out there with road gearing to take you around the world so why resort to mountain bike gearing.


-because IIRC as you said, you asked for those chainring sizes. If you look at all the chainsets that support those you will find dozens that are MTB ones and just a few that use a road chainline. Plenty of people do use the MTB ones quite happily on touring bikes and wouldn't consider it a problem. I am not in that group and I know that because I've tried both.

You really do yourself a disservice by resorting to this kind of comment as I am not getting worked up about it but rather just openly discussing my opinions of it and perhaps at the same time trying to influence others that may be thinking of having a bike built considering their decision before spending out a lot of money.


well your intentions may be laudable but; a) you have taken my comment out of the context of the analogy in which it was placed and b) accusing the bloke that built your bike of 'making it the lowest possible quality in order to extract the largest possible profit' or somesuch isn't so much an 'open discussion of opinion' as it is something else altogether.

If only I had read Robert Penns book " Its all about the bike " who funnily enough also rode around the world on a Roberts but then chose to buy a custom made Brian Rourke, before buying my bike.


any bike you build or have built ought to be a personal journey of some kind. Personally I found Robert Penn's choices bizarre and inexplicable in many cases but if he went into it with his eyes open, he got the bike he wanted at the end of it and he was happy with it that is good enough. If he turned round at the end of it and said that Brian Rourke's paint job was revolting and overpriced (or something) how much sympathy do you think he would get bearing in mind that this was exactly what he asked for?

One final comment I cannot help but think having read many of your threads and comments and the vast knowledge you appear to have that you in reality you are a bit more than a " cyclist " and possibly a professional bike builder yourself and that is why you seem to get a little touchy when their abilities are questioned on the forum.


that you might think that is possibly symptomatic of something else altogether. I've tried my best to help other people choose the right kit because it isn't always easy to do that. My profession is that I am a materials scientist; bicycles are just a hobby.

I happen to own a frame from the very same builder and in the 30 years I've owned it, it has carried me many tens of thousands of miles with no worries of any kind. My experience is similar to that of many other owners. It has, over that time, cost me less than 10p a week to own that frame, so how anyone could call it 'overpriced' I cannot see. In point of fact it may not even be my 'favourite bike frame' but it is the best one I've ever owned for its intended purpose; had I not been clear about that purpose or perhaps have had unrealistic expectations of some kind then perhaps I might have been disappointed; but even then, that would just have been a state of mind, and nothing to do with the quality of the bike or its true 'value'.

cheers
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CJ
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Re: Larger Chain Wheel & BB

Post by CJ »

hondated wrote:Given I wanted a touring bike there are more than enough bikes out there with road gearing to take you around the world so why resort to mountain bike gearing?

When I was reviewing touring bikes I always criticised those that were built with road gearing. Reason: the number of enquiries I got from people who'd bought a bike like that and needed lower gears than is provided by the same size ring and sprocket - which in most road systems is about as low as it gets. I also observed how people who turned up on my tours with a bike like that, struggled painfully on the steeper hills, and these were two-week hotel tours, not camping round the world!

Those gears may be okay for the young and strong, and those brave enough to stick to well-graded main roads, avoiding the wickedly steep little lanes the rest of us are literally driven to use, but they don't go low enough to make hills easy enough that normal people can enjoy riding up them. I'm glad that those gears are low enough for you, hondated, but they don't go low enough for very many people.

In countries where riding bikes is a normal activity, such as Germany, where one in three people go cycling on their holidays, the standard type of bike used for everyday transport AND cycling holidays, is a trekking bike. This uses MTB-style componentry, albeit with somewhat larger chainrings, but nevertheless achieves substantially lower gears than available in any road group. But even those are not really low enough for UK, where cycling conditions are much worse than on the continent. So we must 'take to the hills' and given that 700C is a bigger wheel already than most MTBs have, I reckon the gears are bigger enough already with the same size chainrings as MTBs have, but that's detail. If you've got trekking equipment already your options are open for lower or higher gearing as you please. So that's what I like to see on a tourer.

The snags with trekking/MTB equipment on a tourer is a much wider than necessary pedal track (Q-factor) and consequent misalignment between chainset and sprockets, often resulting in rough running in middle and big, that tends to be a much-used gear. And given the Anglophone tourist's traditional devotion to dropped handlebars, we also have a problem with the hit and miss compatibility between MTB/trekking mechs and road shift levers.

All of those incompatibilities can be resolved, but only by choosing one's components very carefully indeed, usually entailing third-party, non-groupset, square-taper cranks, and by sacrificing some of the extra features offered by complete systems, such as front indexing.
Chris Juden
One lady owner, never raced or jumped.
LuckyLuke
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Re: Larger Chain Wheel & BB

Post by LuckyLuke »

Hi Hondated,

Lovely bike you have there, hopefully sorting the chainset is the missing piece of the jigsaw puzzle.
For what it's worth, I've found the following combos work well with bar end shifters or 9 & 10 speed Campag Ergos:
Campag square taper triple, 135/74 BCD (49/39/26 rings.).
Stronglight Racelight triple, 130/74 BCD (48/38/24 rings).
I used these with campag triple front mechs, or the Shimano flat bar one (?R443).
Both take Campag square taper bottom brackets, 111mm IIRC.
I've used these on audax style bikes, so they might be geared too high for you if carrying a load (certainly too high for me).

On a touring frame used for laden commuting (135mm rear hubs, MTB cassette & rear mech) I've used Stronglight's square taper Impact triple, 110/74 BCD (46/34/24 rings).
Shimano flat bar front mech as above.
?122mm UN55 bottom bracket.
Worked well with flat bars and flat bar shifters (Shimano's 8 speed ?R443) or 10 speed Ergos
(I used to run it with flat bars and V brakes in the winter, & with Ergos and cantis in the summer.)

Best wishes,

Luke
Brucey
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Re: Larger Chain Wheel & BB

Post by Brucey »

LuckyLuke wrote: On a touring frame used for laden commuting (135mm rear hubs, MTB cassette & rear mech) I've used Stronglight's square taper Impact triple, 110/74 BCD (46/34/24 rings).
...


FWIW I would suggest that is a practical choice for Ted's touring bike because there is very good availability of 110mm BCD chainrings in various sizes. It may take a few goes with BB length selection to get the chainline/chainstay clearance right. A downside is that the inner chainring can't be any smaller than 24T so the low gears won't be as low as before unless you also get a different cassette.

Suppose that you run (say) 48,38,24; this may suit you inasmuch as

-when unladen you may as well have a 48,38 double and

-when laden you may as well have a 38,24 double; (the 48 T ring may only see a lot of work on the downhill sections).

cheers
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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

Thanks Brucey, Chris, Luke I tried out the 48 - 36 - 26 and it seemed ok and require a lot less effort from me as I didn't need to spin as much. However Chris I do appreciate what you are saying about needing lower gears if I do ever get to set off on that great cycling adventure, I really need to do , I will keep the 44 gearing in my parts box for the eventuality.
Luke its funny you suggested 46 - 34 - 24 because Colin has also suggested that so some time down the road I may even try that. As you say Brucey I may have to try various BB lengths to get it right.

I am not particularly looking to blame anyone but do any of you think that the 22 - 34 was a bit of an overkill.

And I should add to be fair to the bike builder one of the things I have just remembered I did stress was that I wanted the cables under the bar tape so that obviously limited what levers he could use.
LuckyLuke
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Re: Larger Chain Wheel & BB

Post by LuckyLuke »

hondated wrote:
I am not particularly looking to blame anyone but do any of you think that the 22 - 34 was a bit of an overkill.

Hi, some folk of this parish do run such gearing when loaded to the gunnels.
Do you find yourself using / needing that combo? 34 X24 is quite close though. Best wishes, Luke.
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hondated
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Re: Larger Chain Wheel & BB

Post by hondated »

Not really Luke but I might on a loaded tour over a mountain. Although I once met a tiny girl on a loaded bike in the Alps who when I asked her how she climbed all the mountains said I am just stubborn and I turn the pedals as slowly as I can. Ted
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