frankenbike's frankenbikes

Hey all, new here, looking for a bit of advice as you seem like a knowledgeable bunch...

I've acquired a horribly garish 26" Marin MTB frame, which I was looking to turn in a pub bike/frankenbike/monstercross/fixie/beater thing. I'm trying to do it on the cheap, and I'm wondering what the best way to go about it is. I think I have 5 or more options mainly related to wheel sizes and I'd like to know what you think will be the cheapest/easiest.

Parts I have already, or have bought:

• 3x8 Microshift/Shimano groupset (inc. STI levers, brakes, crankset, BB, cassettes, derailleurs)
  
• cheapo wheelset with Shimano spline that I built myself
  
• 700c fork with canti posts, quill stem, bars - all for £30, mostly new. Will return if not needed.
  
• decent cantilever brakes that I've been given for free
  
• a 42t single-speed chainring, which will in theory fit to the Shimano cranks above
  
• seatpost to fit this frame (£5) plus two spare saddles
  
  

My options for converting this thing, as far as I can tell:

Option 1: 26" front and rear wheels with 3x8 groupset
The cheapest option (?) but by far the least cool. What I'll need:

• wheelset (£10-20)
  
• tyres (£10)
  
• new bars and stem (£20)
  
• effort required to remove seized stem from existing fork. Really not keen on doing that.
  
  

Option 2: 700c front and rear wheels with 3x8 groupset
Second-least cool option. Seems horribly expensive for an end result that's pretty un-exotic. What I'll need:

• Brake post adapter or long-arm V-brakes for the back (£36 on eBay)
  
• A travel agent device (£15 on SJS)
  
• Fork, bars, stem (purchased already for £30).
  
  

Option 3: 700c front wheel, 26" rear with 3x8 groupset
Now we're getting into the crazy stuff. Handling would almost certainly be awful but it would get major comedy points. Relatively cheap. What I'll need:

• 26" rear wheel and tyre. (£15?)
  
• Fork, bars, stem (£30).
  
  

Option 4: 700c front wheel, 26" fixed rear
Even madder. This one I'd be sort of worried about riding. However, it does have the advantage of two brakes. What I'll need:

• Either a pre-built 26" fixed rear wheel, which doesn't seem to exist, or
  
• Track hub, spokes, 26" rim, build a questionable wheel myself (£30+)
  
• 26" tyre (£5)
  
• Cogs (£0 - £5)
  
• Fork, bars, stem (£30)
  
• Single speed levers (£0 if I use my STI levers, £5 off eBay)
  
  
  

Option 5: 700c front wheel, 700c fixed rear
A proper single speed, but no possibility of a back brake. What I'll need:

• Fork, bars, stem (£30)
  
• 700c fixed rear wheel (£10?)
  
• Cogs (£0 - £5)
  
• Single speed levers (£0 - £5)
  
  

Option 6: Just buy a fixie and chuck this frame
What I'll need:

• Fixie (£100?)
  This frame is truly horrid and I doubt I'll be able to find anything else as nasty for sale. Which would be a shame.
  
  

Other things I'm thinking about:

• fitting caliper brakes on the seat-stay bridge and using a 700c rear. The hole is drilled the wrong way, but there's probably a way to make it work? I could even just make something that bolts to the seatstays. Would solve a lot of my problems.
  
• I like down-tube shifters, and with any of the 3x8 options I could switch to them (£15 on eBay).
  
• if I get 700c wheels, I might fit fat CX tyres so I can ride it anywhere.
  
• would love to chuck a front rack on that fits to the brake posts.
  
  

What would you do in this situation? Do you know of any cheap bits going that'll help me get this working? Is it an all-round terrible idea?

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The frame is rad, I'd go with 26inch front an rear and some wide schwalbe kojaks. As for drive train i'd go ss, fg or 1/x for city beater pub purposes. Definitely use the original bars and don't cut them down. A stem with more rise might be more suitable, it's also easier since it'll have the canti cable guides. The seatpost looks heavy and impractical, get a one piece kalloy seatpost (they're available in various diameters) and a beater flite or turbo saddle.

Glad I'm not the only one who thinks so! It's been sat in the sun so long that the paint has faded on the top which makes it look really odd. Bright yellow from the underside and where it's been covered by parts.

re. bars, I'd much prefer drop bars, but the original ones do get cool points for the yellow. Would have to buy flat-bar brake levers if I keep them.

And where would I find a 26" fixed/single-speed rear? I could buy a conversion kit and a normal splined wheel but if I'm going SS it seems like a waste to not have the option of fixie as well, don't you think?

Rad frame! I'd go with an 1x setup, 26" wheels and wide ass tyres.

What @vp1337 said. Wouldn't bother with fixed unless you're eager to build a specific ss/fixed wheelset

Won't I trash my chainrings/chain/cassette/derailleur with a ghetto 1x8 setup though? I guess I could buy a new derailleur if the pull ratios are the same.

I would like to get myself a fixie... this is already my third bike though, and it's going to have to live outside, unlike the other two. If this one doesn't get turned into a fixie I can't have one until I buy my own flat or move somewhere with a garage (years off). Maybe I'll go 1x for now and keep an eye out for the requisite fixie parts and have it as a long term project.

Also, the seatpost and purple fork in that photo are spare parts that I thought might fit (they don't).

The original stem is in the top right of the photo - I had to saw it off. The other half is still firmly stuck in the steerer tube. You can see it if you get the full-size photo.

Have also just noticed the writing on the frame... looks like it says "DMG?" As in damaged? That could refer to the fact that the stem is seized though - it looks to be in pretty good condition aside from that. No major rust issues as far as I can tell and no cracks.

In addition to my earlier comment, if you want it to be fixed and or singlespeed go for it! But keep in mind you won't be able to find anything otp. What's the wheelset you already built?

Just a crappy road wheelset. Buckled a rim, bought a new one (naively assumed it would be the same size), then when it obviously didn't fit I had to buy new spokes and build it up. Took me a good while but I've ridden on the wheel and it does the job, just about. In fact I took it to a local shop to check over once I'd finished it and he said I'd done a really good job which I was pretty pleased about.

I kind of think wheel-building/truing is something that you can't really have too much practice at. It's very tedious when you don't know what you're doing obviously, but it's a great skill to have when you pop a spoke miles from home (which I've done).

Having said that it's not something I want to do if I don't have to. Maybe slightly preferable to removing a seized stem.

As you say it is a skill that worth your while to learn. Single speed wheelsets are the easiest to build and the internet/wheelbuilding thread is always there to help out. You'll probably be going over your reserved budget if you go down that road

Yeah I think you're right, probably a lot easier and cheaper to just find an old rim-brake 26" wheelset. They've gotta be ultra-cheap these days.

For 1x I'm definitely going to need a clutch derailleur at minimum right?

I think a chain catcher might be the cheapest option cause with a clutch mech you'll also need the appropriate shifter. Not sure... You can try the 'Any questions answered' thread for a definite answer

I’ve turned a’91 Raleigh ‘531’ MTB into a drop bar tourer, inspired by http://www.bikeforums.net/classic-vintage/828426-show-your-vintage-mtb-drop-bar-conversions.html
Mine’s on p.225 - bars look a bit odd due to the camera angle. I’m used to it now & it`s been great on local lanes in the ploughing season muck - probably not a problem in the city! Good luck with it!

Definitely some very nice bikes in there... Probably out of my budget to put together anything that beautiful! And a bright yellow frame isn't ever going to be understated.

But I like the idea of a MTB/tourer conversion - seems like the way to go for now. Did you stick with 26" wheels?

I have a lot of the parts you might need; including friction thumb shifters...

Let me know if you are interested

Ah , just re read the post and see that you have assembled many of the parts.

This is a 26" wheel bike and it won't work with any thing else ..

How much are you after? Are they bar end or down-tube? Are they indexed? I like the non-indexed ones, and I'd be able to use any old derailleur that way too.

I should have mentioned I'm in Edinburgh, so if I wanted to get any parts they'd have to be posted.

+1 buy a 26" wheelset and either 1x8 (just buy a chain catcher) or single speed.

Maybe treat yourself to some modern canti's too like Tektro cr720 (you can pick them up cheap.) or some cheap cheerful v-brakes.

How have you already tried to get the stem out? Might regret taking a saw to it so soon ....

Joy;

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Those things are sweet! 26", drop bars and c h u n k y b o y tyres it is!

Thinking about it I will be getting (most of) a SRAM X7 derailleur in the post soon. It would definitely be much more amenable to a 1x front chainset. Just need to replace the jockey wheels, and would also need a friction shifter and brake levers.

Brakes - I'm being given some cantis from Charge Plug which I'd expect will be decent.

The stem - it is seriously wedged in there. I've been trying to remove it for the last week. I've already cut it off at the top, and have been cutting out a slit down either side the past few evenings. Finally managed to force it away from the wall of the steerer tonight so hopefully with a bit of WD40 sat in there overnight I'll be able to finally get it out tomorrow.

This is mine. 1x7 and loads of fun. Gonna get fatter tyres once I've gone through these 26x2.0 at the moment.

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@dazzrie - love it! Some great inspiration here.

Regarding 1x...

Had a good offer for two 9-speed MTB cassettes to match my partial X7 derailleur... A bit more research and I found out that the cheap eBay Shimano friction shifters (e.g. Dura-Ace SL7700) don't pull enough cable for SRAM 9-speed derailleurs. Of course. So that would mean buying a proper set of shifters.

I also have a SRAM Rival 10-speed derailleur - if I've only got one front ring it could probably take a slightly bigger range at the back, right? So I might be able to go up to a 11-32 or something. But again, I'd need new shifters - maybe some cheap SRAM 10-speed TT levers. This is a good option as it would mean that in the event my serious road bike breaks, I could cannibalise this bike in the short term. (My proper road bike is soon-to-be converted to 10-speed SRAM with MTB cassette/RD and road front stuff - a touring setup. After cycling round Skye/Outer Hebs. with 20kg of camping gear I decided 30/28 wasn't low enough.)

Also wondering if my MicroShift rear mech can take a wide-range 9-speed Shimano cassette... I think the wrap would be okay since it works with a triple, but not sure it's got clearance for the big cog on the cassette.

Maybe I should just stick with 1x8, 11-28 rear, 42 front. 42/28 seems stupid considering I've got 8 whole gears though. Although the smaller wheel means it's more like 34/23 on a 700c wheel. Not as low as I'd like considering how heavy this will probably turn out but I could probably manage.

If you do go for drop bars it’s a good idea to have the correct cable pull to suit the v brakes or cantis - I got these & they feel really nice & only £18 at the moment:
http://www.wiggle.co.uk/tektro-rl520-drop-bar-brake-lever/
or if you’re quick a set for a tenner on ebay http://www.ebay.co.uk/itm/Tektro-RL520-Drop-Bar-Brake-Levers-Silver-/282652115147?_trksid=p2141725.m3641.l6368
My original cantis were in a state so gave up & got some V brakes which were a doddle to set up & sit over the biggish mudguards well. I’ve got a stronglight triple with 52/46/32 but the outer ring is just as a bashguard really, though it will pick up the chain. I haven’t managed to push 52-11 yet! It may as well be single speed as I’m in the 46 all the time.

You can pick up 9spd and 10spd SRAM mtb trigger shifters for about 10-20£ on eBay and here. 10 speed stuff tends to be more expensive (chains, replacement bits), and doesn't increase ratio over the cassette (just an extra mid-block sprocket). SRAM 9 speed and 10 speed is interchangeable between Road and MTB, so you can mix derailleur / shifters / cassettes without any compatability issues.

X7 (10spd) has stated max of 36t, unsure about 9 speed but think it's the same. Rival 10 speed (short cage) are recommended to 28t, med cage version to 32t ... Might be easier and cheaper to get a cassette that maxes your RD and if you feels over or under geared experiment with chainrings. Easier than fucking about over-reaching your derailleur (can be catastrophic for your hanger / frame / derailleur).

But really it depends what sort of riding you're doing and where you live. If this is a pub bike as you've said, don't sweat it, just buy whatever.

Shifters; https://www.lfgss.com/conversations/310533/#comment13860164

I live in Edinburgh which isn't the flattest. But I could probably manage fine on 42/28 I reckon... On my other bike when I'm riding around town I tend to freewheel in 39/21 or 19 most of the time which is lower than 42/28. It's just a question of whether I'll ever want to go anywhere that isn't the office/pub/shops/etc. I guess I should assume that I won't for now and decide to upgrade later if necessary.