changing to a triple

[flobber]

Hi, been hankering after a triple chainset to help on some of the hills (not in the vale of belvoir, but as I go further a field).

If I go from double to triple I know I need to change the front and rear derailier, but am I likely to need to change the BB as well. Its relatively new octalink (can't remember the numbers, but now appreciate why it is a good idea to write these down before installing!)

Also looking to move up from 7 to 9 speed. If I'm changing the rear derailier anyway, can I change this to something with a 30 on it for the bigger hills?

Thanks for responses.

[gaz]

If I go from double to triple I know I need to change the front and rear derailier, but am I likely to need to change the BB as well.

Probably. Have a look at the area around the chainrings, chainstay and bottom bracket. Can you imagine extra spacers and a third ring on the inside. If you can't imagine it then there's probably little hope.

If you can imagine it then it might work, but there's still the question of chainline.

[Mick F]

You're obviously Shimano with Octalink, so I'm not the best adviser, but others are.

However, what gaz says seems correct to me. Some BBs will take a triple if there's enough room, but you may need a longer BB.

Also, front and rear derailleurs MAY have enough capacity for a triple, but then again not.

Basically, what I'm asking, is for you to state EXACTLY what you've got now - ie bike plus equipment.

If that's all known, a plan of attack can be discussed.

We look forward to the info!

[drossall]

Also looking to move up from 7 to 9 speed. If I'm changing the rear derailier anyway, can I change this to something with a 30 on it for the bigger hills? Thanks for responses.

Don't quite understand the question. The derailleur doesn't have a 30 on it - that's the block (cassette or freewheel). If you have a screw-on freewheel, you won't be able to get a 9-speed version. For that matter, if you have a 7-speed cassette, a 9-speed won't go on the same hub. Either way therefore you'd need a new back wheel.

As far as derailleurs are concerned, standard ones accommodate up to about 26 teeth on the largest sprocket on the block. The cage on the derailleur just won't clear anything bigger. For a 30-tooth sprocket, you'd need a long-arm derailleur.

There's an important second aspect to this. The triple and the larger block are each going to increase the difference between the length of chain needed to get round the smallest sprocket and smallest ring, and the length needed for the largest and largest. When you change between these combinations, the extra chain length has to go somewhere. It's taken up by the derailleur cage swinging back and forth. The long-arm cage is also able to take up a greater length of slack chain when you change gear.

Hope this is clear. Basically you're looking at replacing your entire transmission and back wheel. The cost will be significant enough to make you consider spending the money on a new bike (and keeping the present one for bad weather or commuting or shopping or whatever).

[rgc_911]

Hi Flobber,

how about changing to a compact double?

I assume you are 52/39 on the front with 130mm bcd (the diameter that the bolts attach the chainrings)

I changed to a 50/34 recently - would go straight on if you stay Octalink as long as it's not a 1 piece crank/bb that you have already.

You can't go any smaller than 38 on 130bcd, so compacts are 110bcd
(i.e the chainring bolts are set on a smaller 'circle')

You would possibly have to move the front derailleur down a touch (or you might get away with it)

this would reduce your lowest gear by around 10%. I had a 14-28 7 speed cassette on a hybrid - you can still get them in Decathlon (Sachs branded) so you might want to change that but even so you will avoid the major change from double to triple.

If you have 7 speed STI's (or any indexed shifters) you would have to change them as well for 9 speed - if you have bar end or downtube shifters then switch them to friction and you will be fine but won't get indexing.

It's a major change - are you sure the bike is worth it?
Merlin do a 10 speed 105 groupset for £230 ish and a pair of wheels would be around £50-80 for something 'reasonable' (eg Tiagra)

I got an FSA MegaExo compact crank AND bb for £55 on Fleabay - job done (once I'd borrowed the correct BB tool)


hope that helps

cheers
Cookie

[reohn2]

If you go for a compact chainset you're limiting yourself to using the big (50tooth upwards)ring for 80% of your riding.The inner ring is only (with 34teeth)any good for climbing,which is quite limiting especially if you like to trundle along at 15to18mph.
If your funds are limited(who's isn't)I go for 38tooth inner ring (but check the chainset,not all Shimano will take 38t, later ones only accept 39t.A long cage mountain bike rear mech and wide range cassette if the hub will accept 9sp,if not your limited to 7sp,which are available with 30t bottom gear but the gaps between gears are bigger due to there to not being as many sprockets.

The triple route will be costly if you need a rear hub along with c/set(£50),BB(£15),front and rear mechs(say Tiagra £35),chain and cassette(£35).

[drossall]

Or buy a Stronglight and get a sensible outer ring in the first place. Somewere such as SJS or Spa Cycles should be able to sell you a 46/34 even if they don't list one.

[rgc_911]

The triple route will be costly if you need a rear hub along with c/set(£50),BB(£15),front and rear mechs(say Tiagra £35),chain and cassette(£35).

and that's assuming the shifters are compatible - if not add £80 for Tiagra 9 speed STIs, or £35 for bar end, plus a new rear wheel to take the cassette.

Yes you can change the outer on a compact, but I got the impression it was the lower end that was a problem, and 38 is not that low.

I ran 42/34 on a cyclocross bike last year, and was way better than the 48/38 it came with, but it cost £30 for the outer ring (a TA from SPA) but only £55 for crank (with rings) and BB.

If 34 turns out not to be low enough, then you can go 30, which is the same as my triple has anyway. (can always swap them around for a specific trip etc)

I was faced with a similar upgrade on my hybrid - I sold it and got a 9speed bike - it would never have been worth what I'd have to have spent to convert it. (probably should have kept it as a hack for what I got for it though)

cheers
Cookie

[flobber]

thanks all for the replies.

To conclude....It is for a bike that was given to me by father in law. Its about a ten year old peugeot. Its a reynolds 525 frame and is generally pretty nice to ride and quite quick.

The stuff that is on there is all Exage (I know its old, don't laugh, it works) ranging from exage 300 - 500. It a 14 speed ...currently a full size (is that the right term) sora on the front. Which I put on as I wanted to get rid of the biopace thing without spending too much money as I wanted to see how I got on with this type of bike. It has a 7 speed cassete on the back (11 - 26) I use all of these.

My reason for asking was becuase I am starting to clock up quite a lot of miles, I'm regularyl doing 70+ rides as well as around 100 miles commuting miles...basically by the end of the week my legs are tired and I struggle on the hills!

I have looked at the prices of changing the bits and pieces. I think if I went for a compact and it worked, then it would be fair enough. But beyond that I'd be looking at shelling out something like 300 notes. I don't think it is worth it. Just a shame, I don't like to spend money unless I have to....not skint, just tight!

[reohn2]

I totally forgot the shifters which makes it even less of an option,
As for a small outer ring on a compact,be careful with a less than 48tooth outer ring, modern road front mechs don't like anything less than 48t usually.

[rgc_911]

Its about a ten year old peugeot. Its a reynolds 525 frame and is generally pretty nice to ride and quite quick.

sounds like a classic -with a biopace too - very period

I'd be tempted to keep it as original as poss.

basically by the end of the week my legs are tired and I struggle on the hills!

In 6 months time you'll be fine - I bought a triple, but never use the 'granny' ring at all now - should have got a double - lighter and much easier to set up.
Zero cost and you'll be fitter too!


cheers
Cookie

[ddddddd]

There is no reason to keep the bike "original", if that configuration is not useful. Unsuitable gears won't necessarily be solved by getting stronger. Depends on the hills, really.

As for zero cost:
Find someone who doesn't use their triple inner ring and swap parts with them. [Mentioning no names.]

More realistically:
A new rear derailleur doesn't have to be expensive. Get one sold as "mountain bike" type. Combine that with a wide range rear cassette and you will get some more useful hill climbing gears. Assuming you have a 39T front, then going up to a rear of 34T, which is the largest standardly available, gives approx. 30inch gear.

It gets a bad press here, but for day rides without much luggage, consider a Megarange cassette. This has one gear much lower than the second-lowest gear. (7speed Megarange cassette 11-13-15-18-22-26-34) I don't know if these are still available, but the good thing about the cassette system, is that it allows a high degree of customisation. You can swap cogs and try out your own gear combinations.

[hamster]

SRAM are now doing a 12-32 7 speed cassette which is very handy for luddites like me who refuse to 'upgrade'...ChainReaction and Spa both stock it.

[meic]

I disagree with Reohn about the compact double. I had a 50/36 compact and I spent more time on the inner ring than the outer one.
I probably pedal faster but lighter than Reohn, what style suits you?

[pete75]

Hi, been hankering after a triple chainset to help on some of the hills (not in the vale of belvoir, but as I go further a field).

If I go from double to triple I know I need to change the front and rear derailier, but am I likely to need to change the BB as well. Its relatively new octalink (can't remember the numbers, but now appreciate why it is a good idea to write these down before installing!)

Also looking to move up from 7 to 9 speed. If I'm changing the rear derailier anyway, can I change this to something with a 30 on it for the bigger hills?

Thanks for responses.

Over the past few months I've upgraded a late 80's British Eagle Touristique from 12 to 27 gears. I've spent about 60 quid in total.

First thing I did was change to triple. New bb with longer axle - forgotten the exact length, 28 tooth inner ring , and triple bolts - all for Stronglight LX100. Total cost £23 from Spa cycles who still have proper Stronglight cup and cone BBs in stock.

Had a back wheel with an old Uniglide freehub and 6 speed cassette. Bought a new Deore hub from Rutland cycles - on offer for £7 and replaced just the freehub on my wheel with the deore 9 speed one. The uniglide and hyperglide freehubs are interchangeable. Fitted an HG50 9 speed 11 -34 cassette(£8.99) again from Rutland. My frame is 126 spacing and I'd estimate my new hub setup is about 128 so still goes in easily. Bought some dura ace bar 9 speed bar end levers off ebay for £19. You should be able to change just your 7 speed freehub for a 9 speed one and it costs less to buy a complete rear hub than a freehub on it's own. Rutland still have the Deore hubs on offer in their ebay shop.

It all works well and indexes with my original front and rear gear mechs which are late 1980's Suntour accushift - don't know the exact models without looking. Front rings are 48, 36, 28. Before I changed to 9 speeds at the back I was using a different back wheel with a 7 speed shimano "mega" freewheel and the rear indexed perfectly well using the 9 speed bar enders. Of course if you really want to save money and have downtube levers which are switcahbel to friction you could use those. It'd be a bit awkward at first but once you got used to it would be fine.

Chain is kmc z82 8 speed which I had in the garage.

I'm sure there are experts here who'd say the above shouldn't/wouldn't work - all I can say is I've done it and it does.
I could have spent a lot of money changing from 12 to 27 but I thought I'd try what I've outlined above first. After all everything I'd bought would have been needed for 27 speed anyway along with a lot of other stuff. Differences in spacing are fractions of a millimetre which are often neither here nor there with something as crude as derailleur gears - many things in engineering which don't work in theory work in practice and vice versa.

Incidently when I bought the stuff from spa cycles the guy on the phone said double front mechs often work better with a triple set up than triple ones do...