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Posts Tagged ‘converting a mountain bike’

 

commuting - newcastle street art

commuting – newcastle street art

This is my one and only ‘road MTB’, a 1990s Giant Boulder 550. I’ll be frank, I like it mostly because it has a classic horizontal top tube, a nice purple single-colour paint job ( even if a little worse for wear now ), and while being too big for me as a mountain bike it’s an ideal size for the road with a 60cm C-C seat tube and a 59cm top tube.

the non-drive side

the non-drive side

The actual seat tube is almost 63cm C-T which means that I can run the saddle and bar tops almost level with each other for comfort, and I have a good reach with just an 80mm stem. The lack of stand-over height doesn’t concern me here, I can touch the ground with one toe from the saddle and I tend to ride cautiously in stop/start environments anyway.

From the previous rebuild I have retained the Panaracer Ribmo 26 x 1.75 tyres and Tektro RL520 V-Brake drop bar levers. The RiBMo tyres are tough and fairly heavy, being peaked in the centre with a thick layer to help against punctures, and so they ride on a narrower footprint when vertical and a wider one when leaned over.

After some riding, I felt that my last build wasn’t quite right, and it has taken a little time and the right parts to figure out the improvements. It might be noted again that this frame was found as hard rubbish, with no wheels or seat post. The only original bits are the frame, the fork, and ( now no longer ) the rear Acera-x derailleur. The original cantilever brakes I had long since replaced with the more efficient V-brakes and the riser stem and flat bars disappeared with them.

This latest version’s adds are :

suzue promax 36h

suzue promax 36h

A new Suzue Promax 36H front track hub – it has very smooth bearings, solid high flanges, and is really good looking with its opaline decoration. Rear hub is a recycled Joytech – it’s one of their better ones for thread-on freewheels, but they have made some junk also … Rims are Sun MC18, also recycled, with 2mm plain spokes.

Recycled Winpista alloy bars 41cm c-c with black KT leather tape and SR 80mm stem. Wider bars wouldn’t really suit here as there is plenty of leverage with this frame geometry.

sakae custom 52/36

sakae custom 52/36 double

The major change though has been the chain set – the triple ring 48-38-28 has been replaced by a recycled Sakae (SR) Custom 52/36 compact chainset. Although it only has swaged on cranks and a non-replaceable ‘big ring’ this is a much simpler and lighter rig. The old 48T big ring was too low for the 6-speed (14-16-18 -20-24-28T) freewheel cluster, at least for the lower overall ‘geared’ 26″ wheels . 52T is much better on the flat or down hill with the 14,16 or 18 cogs. The 36T small ring is a bit low when the going is easy, but great on slight inclines or strong headwinds at 36 x 16T or lower. I would like a 13T small cog on this, perhaps as a 7-speed, as the 52 x 14 is only just high enough for downhills, but I don’t want to lose the 28T low gear. ( Note – I have since fitted a 7-speed cluster 13-28T and changed to friction shifters and that has improved things greatly when in the small ring ).

Compact chainsets seem to do better with a large range of rear cogs to avoid having two nearly completely different sets of ratios. This avoids excessive shifting between the front rings which was happening here while running as a 6-speed.

For a moderately fit person the 36 x 28T will climb up a decent hill without trouble, while eliminating some of the weight and complexity of the triple.
Bottom bracket is now a Gist 110mm sealed square taper to suit the new chain set.

This model MTB originally came with a micro-drive triple chainset ( 38-32-24 – tiny rings ) and an unusual front derailleur that was integrated with the BB and cable operated from above. It did take some fiddling to fit replacements as the original chain set was worn out. At least the seat tube wasn’t oversize for a standard band-on derailleur but the cable had to be run in an outer, which is cable tied on to the down tube. The 16 tooth up-change from the 36 to 52 rings took a degree of care and was a bit clunky compared with, say, a 42/52T – as one would expect.

I swapped a to a better ‘recycled’ Shimano front derailleur and fitted a new Tourney ( basic ) rear derailleur and some new Jagwire gear cables to try and improve the shift. Along with the smoother friction shifters this has been successful.

great levers

great levers

I have settled on stem shifters as I’m not fond of the original revo-shifters which don’t fit on drop bars anyway. Down tube shifters would be miles away on this frame, and there are no bosses either. Band on fittings would not even fit on the thick tapering down tube.

Only bar-end or stem shifters would work for me here so I have gone with the easy option – and I have plenty of salvaged friction stem shifters to choose from. I find the subtle fine tuning of friction shifters can be an enjoyable challenge, mostly !

The Tektro RL520 levers work really well and are very cosy in the hands. Saddle is a Brooks B17 special “copper” on a 25.8mm Kalloy post. If the bars were lower I would use a narrower model saddle as the B17 really is a touring saddle – naturally, it works fine here.

B17 special - 'copper'

B17 special –
‘copper’

The Brooks small ‘Isle of Wight’ saddle bag  ( above ) is quite discreet and well thought out. My only minor niggle is that it’s possible that the neat toe strap front fitting could scratch an alloy seat post.

The Giant’s small wheels give it a light and quick low speed steering, yet the laid back geometry and longish wheelbase mean that overall direction changes are fairly slow.

It’s arguably the most comfortable of all my bikes ( except the Gazelle Toer Populair ) and it is very versatile. The main frame is 4130 cro-mo but it is still pretty heavy, partly I guess because it’s such a large frame – along with the weight of the wide tyres etc. I notice the weight on hills and when accelerating out of corners, mostly. The small wheels allow a very gentle side to side rocking motion when pressing on ( compared to 700C ) but are quite stable at speed, and very much so through rough corners.

Also, for such a large frame it is very flex free at the front end compared with my road bikes, perhaps because of the wider top and down tubes. These tubes appear to be ‘butted’ on the outside as they are quite noticeably thicker on each end where they form a frame joint.

I can’t exactly tell you what it weighs but it compares reasonably to some modern ‘retro’ steel framed tourers I have lifted up in the shops, though it’s very much heavier than a good steel road bike. To make it significantly lighter than it is now however would cost too much, or possibly reduce the ride quality.

one of my fave 'bike shot' trees

one of my fave ‘bike shot’ trees

I present it here again as an improved example of converting an MTB to a touring style bike, though for my taste only the classic ‘rigid’ mountain bikes have the appropriate good looks to be worth putting this much effort into. Modern MTBs with suspension forks and crazy graphics wouldn’t work as well aesthetically, at least in my opinion.

I guess this bike is nothing special either in appearance or rarity, but it does do many things very well.

Not as quick as a road bike, but its stability, rough road ability and sure-footedness are a joy. On a recent dark and rainy commute home I was only 8 minutes slower over the c.26km than on the previous dry night in spite of taking things much easier, and that surprised me !

Steady as she goes —- and happy Re-cycling !

shot on the morning commute

shot on the morning commute

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ride the bat-mo

ride the bat-mo

That’s what I’m thinking as I ride along on the purple Giant’s back … oh yes, I’ve changed my mind again about this machine and fitted the Tange moustache bars. The drop bars in the previous Giant post felt a little too narrow in the end … but it was fun trying them.

the final version ?

the final version ?

So, how does this setup work ? Well, as it has “v-brakes” – or, more correctly, “linear pull brakes”, you need the appropriate levers, as those for calipers have a different cable pull rate to those for v-brakes. As these bars are like drop bars bent through 90 degrees ( and vice versa ),  road v-brake levers  will still work in the horizontal plane, by having the lever curve following the curve of the bar. This is the only place these levers will work properly on these bars. The other alternatives would be normal MTB levers,  which could impede hand positioning – or perhaps reverse levers on the bar ends  ( designed for v-brakes in this case … if such levers exist  ).

not your average mtb

not your average mtb

Because of the wide range of hand positions on moustache bars it pays to think ahead about where you want to put your levers. In the position I have them here, they are close to hand when leaning forward on the front of the bar, which is generally when riding faster. Levers positioned at the end of the sweep back are easier to access when sitting more upright. The wide range of available hand (and therefore body) positions is one of the best things about these Tange bars – they do take up a fair bit of  space though.

The levers I have used are Tektro model RL520, which are rather nicer to hold and better looking than the equivalent Dia-Compes in this case, and better designed too, in my opinion – the Dia-Compes do however have a neat adjustable noodle for pad wear compensation. The Tektros have quick releases built in, though they are perhaps not entirely necessary on v-brakes, where you can do the “squeeze” and free the noodle by hand, but at least it’s a little easier.

the devil's in the detail -- RiBMo ! ( teehee )

the devil’s in the brilliant detail — RiBMo ! ( teehee )

The Panasonic RiBMo ( Get it ? —> Ride with Batman’s Mo’ … !!!   Groan ! , O.K. I’m sorry ! ) tyres are excellent. They are a folding Kevlar belt 26×1.75″ for urban / commuting use and have a kind of pointed shape in cross section. This seems to give a smaller road contact for lower straight line rolling resistance along with the ability to turn quickly without the drag of more rounded tyres – at any rate, that’s how they feel to me. They appear to be very puncture resistant and have a greatly improved speed and precision of handling – without losing any of the 1.75″ comfort over rough roads. Altogether great 26″ tyres for “Road MTBs” .

let's roll !

get yer happy shoes on and let’s roll !

Regular readers might notice that I don’t do many posts on MTBs – well, they aren’t quite my scene generally, but can of course be excellent all-terrain commuters as we all know. Only please, dear readers – don’t let the following Wardrobe Malfunction happen to you —- it’s what gives MTB riders a bad reputation in some circles ( heehee ! )

OMG --- lovely bicycle, it ain't

OMG — lovely bicycle – NOT !

There goes my last shred of cred …  Bye !

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hi-rise frame

 

 

A current side project of mine is reworking my old Giant Boulder 550 ’90s model MTB. This bike was found as a dumped frameset a couple of years ago and has become the bike that gets all the cast-off bits from my other ones as they are upgraded, as well as various new bits and salvaged old parts .

I overcame my partial dislike of mountain bikes by fitting different handlebars to it as flat bars are really hard on my wrists. I really feel that a swept back bar “holds”  the same way your wrists relax when held at your side.

Other than that MTBs can make fine all-rounders, though I only like old steel ones with horizontal top tubes ( what a snob, you say ! ).

Especially purple ones!

 

v.o. “belleville” bars

 

These narrow Velo Orange Belleville “no-rise” bars should work for me because the large (61cm) frame size means that I can keep the bars high enough relative to the seat, and the swept back grips keep me a little more upright. They also give the bike a sort of old-fashioned “sporty” look along with the high frame and “small” 26 inch wheels.

 

fat serfas tyres

 

Thinking about what I don’t have in my collection of bikes, I decided to give this one a really low bottom gear of 1:1 for when I feel the need to easily climb the steep local grades. So, on went a Sakae triple front ring from a salvaged Apollo (48/38/28) along with a 5-speed cluster and a recycled front derailleur.

A fifteen speed triple is enough for a wide range, and close ratios are not really necessary here.

 

this f.d. required some cable re-routing

original rear mech. and my roughly hand painted “pie plate”

 

The original 7-speed rear derailleur was stop-adjusted to fit the 5-speed cluster and a new friction front/indexed rear  Shimano stem shifter from Vintage Bicycle Rebuilds added ( I have developed a fondness for stem shifters via my Road King rebuild ). It’s a 6-speed click so the first click (top) is a “dummy”

I also had to re-fit a cantilever front brake as the v-brake wouldn’t clear the front guard – a fiddly job …

 

nitto dynamic stem, shimano index (R) and friction (F) shifters

 

The wheels are from another chuck-out, and the guards another again, and so there are at least 4 or 5 bikes contributing here !  The art of recycling …

 

i like the graphics on this model, but only the seat tube is cro-mo, i think !

 

It’s not really rideable properly yet, and definitely cosmetically unfinished, but hopefully gives an idea of what you can do to customise that unloved old wreck in your garage.

 

kinda stylish ?

 

If I have enough time, I would like to make a home-made wooden front rack for it … hang on, did I say enough time …. ?

I’m dreaming, aren’t I  ?

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