Replacing old components

[Haz]

Hi all,
Any advice on replacing old components on an old bike? My old Dawes currently has 12 speed non-indexed Sachs-Huret gears with down-tube shifters - affectionately known as 'suicide shifters' by my friends... it also has old Weinmann brakes with annoyingly designed levers and hoods (the brake cables can't be tucked under the bar tape). It all works ok for now but won't last forever - the rear mech in particular is quite worn and the brakes easily misalign themselves.
I'm slightly worried that there isn't enough lateral room for many/any more gears on the back - is this just me being silly or can older frames not take new groupsets?
I'm probably going to replace parts as a longer term project, buying things when I can afford them! Will post photos when it's all done and lovely
Thanks!

 

[Cycleops]

Hello Haz. You can update the shifters to indexed ones no problem and you can also increase the number of gears if you wish, although some would argue there is little point in more gears. Newer gear will work. How old is your Dawes? Do you know what model it is? You also need to check if you have a rear 'cassette' or a integral rear freewheel. You can install more gears but you may need to change the hub to accomodate. If you want cables running under the bartape you need new levers. I have an old Dawes with eight speed cassette and cables that run under the tape so it can be done. You can buy second hand if you don't want to spend too much.

 

[HovR]

DT shifters aren't suicide shifters, this is a suicide shifter.

Judging by your description I'd guess the bike is around 80's era, in which case the parts probably will last forever (they've lasted this long) and just need servicing/re-adjusting. But with that said..

Your bike will take modern brakes fairly easily, although the easiest way is to buy two front brakes. You'll need to drill out the hole in the rear side of the fork crown to accept the 8mm recessed fitting, and you should be able to use a front brake as your rear brake using the old fixtures/washers etc with no drilling involved.

Levers/shifters are pretty easy to upgrade, although if you're wanting STI's it can be expensive unless you go the second hand route. Most (all?) modern levers will fit on to older bars. If changing to bar mounted shifters you'll need to buy some cable stops to fit on the DT shifter braze-ons.


The front cranks are fairly easy to upgrade if your frame is threaded for an English or Italian bottom bracket, in which case you just change the bottom bracket to facilitate the new crankset. Other types of threading (e.g. french) may need a bit of a work around.

If you have 6 speeds at the back you will almost certainly have a freewheel setup (as opposed to a modern cassette), in which case you will need to change the hub (or entire wheel) to a cassette model. Modern hubs are wider than older ones, so whilst some people report being able to 'spring' the dropouts apart enough to fit a modern wheel, most people cold set the frame to allow the fitting of wider hubs.

Regarding the rear mech, does your frame incorporate a rear mech hanger, or does it use one of the claw adaptors to bolt on to the dropout? With the former it is just a straight swap in most cases (if your hanger is threaded, I've had some french frames that aren't), although if you have the latter you may need to buy a seperate claw adapter to allow fitting of a modern mech.

The simplicity of changing your front mech is dependent on the cable run. If your bike uses a plastic (or metal) cable guide on the underside of the bottom bracket shell, then you will be able to swap the old front mech out for a new band on model fairly easily. If your current front mech uses another cabling method, the easiest (neat) way to fit a new one is to drill and tap a hole (5mm IIRC) in the underside of the BB shell to take a plastic cable guide for modern under-BB cable routed front mechs.

Think I've covered most things there, hope some of that helps.

 

[Brommyboy]

I would just renew the worn components. To change the rear wheel for more gears the dropouts would need widening. To squeeze 130 or 135mm dropouts into the 125mm spread the frame would have to be widened. I still use my 7x3=21 speed touring bike and replace worn transmission components as required. This bike has now covered very nearly 70,000 miles and is sound. The down tube shifters are very reliable and easy to use!

 

[mcshroom]

Any part on a bike is upgradeable, it just depends on whether you want to spend that much.

Your brake levers seem to be the greatest concern to you. These can be replaced easily, either with STIs (combined levers not something you need to visit a clinic about) which will do the braking and shifting, or with stand alone brake levers. Modern brake levers are designed for the cable to run under the bar tape. With very few (and expensive) exceptions, you would need to go to 8sp at the back to use STI levers. This would need a new rear wheel and you may need to respace your frame. Modern road hubs are 130mm (MTB hubs 135mm), and your frame is probably 126mm. As it's steel you can just spring the arms apart a bit though.

Other options are to just leave the downtubes - nothing particularly wrong with downtubes, or to use bar end shifters (these can be either indexed or friction only).

For the rear mech, any 8sp/9sp rear mech should work fine in place of the current one. I would get a mountain bike one (something like an alivo) if you have a large cog on the back (over about 26t) as they have a bit more range than road mechs.

What sort of brakes does your bike have at the moment? If they are caliper brakes (connected through a single bolt above the wheel), then you can get newer dual pivot ones. I have a 1980s bike with Tecktro 358 brakes which are nutted fitting so I didn't need to drill anything on the frame. You need to check the drop from the brakes to the wheel though as there are three different lengths of caliper brakes.

If you have cantilever brakes (brake arms connected to posts on the fork/stays at the side of the wheels), then these can be replaced with new cantilever brakes. Otherwise, if you are fitting braking only levers, you can get V-brake specific levers and fit v-brakes which are more powerful (There are no STIs that pull enough cable to operate full v-brakes at present).

For the chainrings, you will probably have a square-taper BB, and I don't think Dawes played around with 26tpi like Raleigh did, so you should be able to fit any square taper chainset, though you may need a new BB with the correct length spindle.

 

[sidevalve]

If YOU aren't having trouble with the shifters why change them ? Having said that I have a Dawes with downtube shifters [they are indexed however with a 7speed cassette] and they are fine for me however you may have to change the hub [as said above] to fit a new cassette. If you want more gears [each to his own, with 14 I have never needed any more and Northumberland is not flat] it may be easier to change to a triple at the front. You may need to get a new, longer, BB but these are easy to find on E bay.
Not sure what the problem is with the brakes, if you just want to be "in fashion" fair enough but the existing setup if well fettled will work very well indeed. Centre pull type brakes can be very powerfull if adjusted and sorted with good modern pads and even the old sidepulls can do the job. If they keep getting "misaligned" then something is wrong, mine last fine without any fiddling unless I strip them down for a clean or [after a long while] have to do a serious readjust.

 

[Haz]

Thanks for all the very thorough responses! I'll try to get some descriptive photos up at the weekend of the brakes and rear mech. I think the front bits (chainring, pedal cranks) have been replaced at some point in this bike's life as they are not rusty... it's a Milk Race. Reynolds 500, so fairly heavy and also Mo-hardened so may be a little tricky to bend or otherwise alter the drop-outs. But altogether miles better than a kids' mtb.
@ HovR - those look terrifying! I'm going to strip the lot down and give it a good clean and re-adjustment over the Easter break when I will have access to a garage full of tools and a cycling-enthusiast relative who knows more about how to set up the gears correctly, then lubricate it all properly again and see if there's any improvement - like you said if they've lasted this long they're pretty solid!
The brakes are annoying insofar as they're a bit big for my hands as well as the cables-in-face issue, but it's not unmanageable to stop the bike. As I said, it's a long-term project to upgrade parts.Also slightly related - can I just paint over the patches of paint which have flaked off?
Plan for the afternoon - get a bottle rack, spare tubes, chain lubricant and GO CYCLE!!!

 

[Haz]

Just remembered another thing - I heard that putting a new chain on old gears doesn't really work?

 

[mcshroom]

If the chain is too worn, it will wear the cassette/freewheel at the back and a new chain slips when you put it on, especially under load.

You may be ok though, depending on how worn the chain actually is. THere's a better summary of chain wear here: -
http://sheldonbrown.com/chains.html#wear

 

[mcshroom]

If it's a milk race, is it like this one?

 

[Haz]

If it's a milk race, is it like this one?

Yep!

 

[Gravity Aided]

That's a nice looking bike. I think downtube shifters are just fine, but you can get a fitting that replaces them and allows you to use Bar-end shifters. Especially nice for touring, but I find it slows derailleur action due to the longer length of cable needed.

 

[Haz]

First 2 replacements:

Got a catastrophic flat on a ride when neither of us took any spares (last time we do that) - spent 40 minutes clip-clopping back home in cleats, thankfully we hadn't gone too far! So now there's a lovely new gatorskin on the back wheel and a hole-free inner tube.

Will this week be replacing the brake cables - one just popped out of the brake lever during a ride today! Slightly terrifying going back home into the city knowing you only have a front brake. They're also fairly knackered around the bit where you need to adjust them on the caliper - the cable fibre is really fraying.

Seems to be a continuous stream of things to repair at the moment!

 

[biggs682]

the joy of riding retro machines my friend . i must admit downtube levers are no trouble once you get use to them . i have just taken a pr of stis of a retro Raleigh Clubman and refitted the original levers it just looked wrong .

most of the original parts can still be found if you look hard enough and any good lbs will be happy to help you along the way .