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Discussion Starter · #1 ·
Background of me:
I’ve been biking seriously for about 5 years now. I started with triathlons, then changed to cyclocross and now I’m trying some mountain biking. I’ve always owned what you would call “race bikes” you know the like… expensive parts and carbon bits… I’ve never owned your basic commuter that I wouldn’t mind riding in the rain or leaving chained outside a store while I run in for something. I’ve also always taken my bikes to the LBS for repairs and tune-ups. Well I’ve decided to change all this, 2 weeks ago I bought a cheap older mountain bike with intent of tearing it down and rebuilding it as my commuter/fun bike. Since I’ll be doing all my own work I will be able to teach myself how to do my own maintenance and learn the fundamentals of bike building.
At this point I’ve decided a few things that I want the bike to have:
· 700C with 32C cross tires.
· Disk Brakes. Not sure weather I’d like mech or hydro yet.
· Flat bars
· Internal gear hub.
· Straight, low rake fork.
· And finally a basic clean look. Most likely flat paint on the frame with some color complimenting wheels.
Here are a few pics that I’m going to use for inspiration.

Less the white tires..



I used kijiji/craigslist to find this, a Bianchi forte TT. I’m not sure the year of the bike, but based on the rear brakes location (on chain stays) I’m guessing its 1987-1990. It came with Biopace rings and a Shimano 600 derailleur. I’m not sure what the shifters and brakes are because they got a spray bomb treatment sometime in it life. I ended up getting the for 30 bucks.







The first step was to strip the bike. I removed as much as I could with my basic tools. Some parts required a vice and little but of encouragement in the forum of a hammer but eventually came free. The cranks and bottom bracket required special tools to remove (crank puller and a bottom bracket sprocket?) I found these at the LBS and got everything removed.
Picture with my 700C race wheels from the tri bike. Test fit to see if 700C could fit. looks like theres enough room for 32C's


Next step was to remove that old beaten up paint. The company I work for has a glass bead room so after work I suited up and removed the old paint. It was interesting to see the bronze brazing used to weld? the lugs together. After the bead blast I applied several coats of self-etching primer to get a good base for the paint to come later.

You can see the gold brazing really well.

The bike in primer.


Right now I’m waiting for the Alfine 8 speed hub and wheel to arrive so I can test fit. I ordered the disk compatible Alfine hub so I might have to widen the back of the frame to fix the extra wide of the hub. I found a supplier that sells handspun Alfine wheels for only 240.00 pretty good deal I though.
URL="https://aebike.com/product/handspun-pavement-series-2-rear-alfine-i-8-velocity-dyad-black-reflective-sku-we7247-qc30.htm"]Handspun Alfine[/URL]

I’m going to keep updating this post as I go.
Thanks for reading
Cheers,:thumbsup:
 

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weirdo
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6,223 Posts
Looks like a fun project and that frame sure looks a lot nicer without the rusty, beaten up paint job. How are you going to deal with the brakes for the bigger rims?
 

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Discussion Starter · #3 ·
For the brakes I plan to use a 180mm (or 160MM) disk brake on the back. The Alfine hub I ordered has the Shimano center lock compatibility. For mounting the caliper, I'm going to welding on a bracket on to the chain stay or seat stay. Not sure which is better for a secure mounting point.
The disk size will be dependent on the room/location I have to mount the caliper.

I don't intend on using a brake in the front. I'd like to keep the bike as clean as possible.
 

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Great start! I have a lot of friends with similar frames, of course they ride them into the ground, awesome to see someone take care of one and restore it properly!
 

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No longer a hardtailkid.
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1,830 Posts
You don't have disc tabs on the frame, so you can't use disc brakes. Unless you spend a ridiculous amount of money for a floating disc kit. Since it's a commuter, keep it cheap. Don;t go buying a nice wheelset, nice parts, and all the works. If you spend alot of money on it, you will be afraid to leave it chained up outside.
 

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No longer a hardtailkid.
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1,830 Posts
Oh, good luck welding something to mount a caliper on the bike. You may as well get a cheapo ebay rigid fork with disc mounts. For only $30 or so, it gets the job done. Finding a 700c disc compatible rims will be hard.
 

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weirdo
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Sheesh!

Hardtail, he explained two posts before you that he plans to add caliper mounts to the frame. Also, ALL rims are disc compatible. I agree with you that it would be easier for him to scrounge up a frame that was already close to what he wants, but I get the idea that what he wants to do is play and experiment and end up with a finished product that is decidedly his own. A perfectly valid goal, IMO.

Freshjive, take this with a grain of salt because I`m not a disc guy and haven`t paid a whole lot of attention to how people go about it, but the Framebuilding section has had several threads concerning the best routes to add caliper mounts. It seems to me that the most recomended way to go about it is to tie both stays together with a gusset, whether you end up putting the caliper on the CS or on the SS. I`m sure a site search would turn up the information you need. You might also consider buying a prebuilt disc-ready fork and using only a front brake, depending on your terrain. Just a thought.
 

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Ovaries on the Outside
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4,425 Posts
This is an interesting idea. I've thought of doing a similar thing with my Rockhopper, but there are some strong reasons for not doing that conversion...

- You will have to use gussets of some sort for the rear brake. You'll have to get someone to do it for you because you don't want to ruin the frame.

- The spacing on your bike is likely 130mm and most disc hubs are 135. They'll fit, but it isn't difficult to cold set the rear triangle.

- I think the outside diameter of your 32mm cross tires will be bigger than the ~2" tires the bike was designed around. Your BB will be higher and that will effect handling. I do think it is likely your cross tires will fit.

- It is an old school mountain bike, so your head angle is going to be 69 degrees or worse. Getting a low rake fork won't help correct this problem much. Thankfully, there seems to be a fair number of disc cross forks with 1" headtube (I'm assuming). 700c wheels will likely only increase your wheelbase length.

I'm not trying to crush your project, just trying to give you food for thought. I did a 650b conversion on my Rockhopper and it worked, but the handling was much worse than the 26" wheels.
 

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Freshjive said:
Background of me:
I’ve been biking seriously for about 5 years now. I started with triathlons, then changed to cyclocross and now I’m trying some mountain biking. I’ve always owned what you would call “race bikes” you know the like… expensive parts and carbon bits… I’ve never owned your basic commuter that I wouldn’t mind riding in the rain or leaving chained outside a store while I run in for something. I’ve also always taken my bikes to the LBS for repairs and tune-ups. Well I’ve decided to change all this, 2 weeks ago I bought a cheap older mountain bike with intent of tearing it down and rebuilding it as my commuter/fun bike. Since I’ll be doing all my own work I will be able to teach myself how to do my own maintenance and learn the fundamentals of bike building.
At this point I’ve decided a few things that I want the bike to have:
· 700C with 32C cross tires.
· Disk Brakes. Not sure weather I’d like mech or hydro yet.
· Flat bars
· Internal gear hub.
· Straight, low rake fork.
· And finally a basic clean look. Most likely flat paint on the frame with some color complimenting wheels.
Here are a few pics that I’m going to use for inspiration.

Less the white tires..



I used kijiji/craigslist to find this, a Bianchi forte TT. I’m not sure the year of the bike, but based on the rear brakes location (on chain stays) I’m guessing its 1987-1990. It came with Biopace rings and a Shimano 600 derailleur. I’m not sure what the shifters and brakes are because they got a spray bomb treatment sometime in it life. I ended up getting the for 30 bucks.







The first step was to strip the bike. I removed as much as I could with my basic tools. Some parts required a vice and little but of encouragement in the forum of a hammer but eventually came free. The cranks and bottom bracket required special tools to remove (crank puller and a bottom bracket sprocket?) I found these at the LBS and got everything removed.
Picture with my 700C race wheels from the tri bike. Test fit to see if 700C could fit. looks like theres enough room for 32C's


Next step was to remove that old beaten up paint. The company I work for has a glass bead room so after work I suited up and removed the old paint. It was interesting to see the bronze brazing used to weld? the lugs together. After the bead blast I applied several coats of self-etching primer to get a good base for the paint to come later.

You can see the gold brazing really well.

The bike in primer.


Right now I’m waiting for the Alfine 8 speed hub and wheel to arrive so I can test fit. I ordered the disk compatible Alfine hub so I might have to widen the back of the frame to fix the extra wide of the hub. I found a supplier that sells handspun Alfine wheels for only 240.00 pretty good deal I though.
URL="https://aebike.com/product/handspun-pavement-series-2-rear-alfine-i-8-velocity-dyad-black-reflective-sku-we7247-qc30.htm"]Handspun Alfine[/URL]

I’m going to keep updating this post as I go.
Thanks for reading
Cheers,:thumbsup:
I bought a spray bombed bike at a yard sale that looks exactly like that frame.There was no way to identify the manufacturer.I will post a pic when I get one.I am also doing the same thing. all the paint is stripped off it now,have to decide on a color.
 

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Ride,Smile, Pedal Damn it
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552 Posts
Sounds like a fun project. If it proves to be $$$ or a real pain. I'd buy a Mosso fork from E-Bay for $40. Light and cheap. (only available in 1 1/8"). I ran a disc up front and cantilever in back. Most of your braking comes from the front. But i'd try the welding first.
Have fun.
 

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Fat-tired Roadie
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18,453 Posts
Looks like a really cool project. I'll be curious to see how you get the disc tabs on.
 

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Discussion Starter · #13 ·
umarth said:
This is an interesting idea. I've thought of doing a similar thing with my Rockhopper, but there are some strong reasons for not doing that conversion...

- You will have to use gussets of some sort for the rear brake. You'll have to get someone to do it for you because you don't want to ruin the frame.

- The spacing on your bike is likely 130mm and most disc hubs are 135. They'll fit, but it isn't difficult to cold set the rear triangle.

- I think the outside diameter of your 32mm cross tires will be bigger than the ~2" tires the bike was designed around. Your BB will be higher and that will effect handling. I do think it is likely your cross tires will fit.

- It is an old school mountain bike, so your head angle is going to be 69 degrees or worse. Getting a low rake fork won't help correct this problem much. Thankfully, there seems to be a fair number of disc cross forks with 1" headtube (I'm assuming). 700c wheels will likely only increase your wheelbase length.

I'm not trying to crush your project, just trying to give you food for thought. I did a 650b conversion on my Rockhopper and it worked, but the handling was much worse than the 26" wheels.

Hey thanks for your response, You raise quite a few good questions that I had asked myself so far. To address as few:

700c wheels with 32C tires will fit into the bike. I had borrowed a friends rim/tires combo to test it out. The rear fits well and has about .750 between the top of the tire and the seat stay support (where brakes would mount on road bikes). I'm not sure if regular fenders will fit but I have found some solutions if case.

For welding of the disk brake tabs or bracket, I work at a welding shop where we do custom things like this from time to time. I feel that brazing the tabs on might be a better idea. I'm not sure how strong brazing would be for the tabs, but that's something i'll discuss with the welders. I have a micro TIG welder that can get down to the lower amps to ensure we don't blow through the piping.

For the rear hub spacing I plan to spread the rear triangle as you said. To cut down on any torsion twisting or unequal bending it plan to use and expanding clamp. Similar to the one pictured below. Maybe it's a good idea to heat the chain/seat stay before bending?


As for the geometry and handling, I think you got me. I'm defiantly going to be raising the center of gravity of the bike witch will have a negative affect of the handling. I wighted out the options of getting a better frame (one designed for what i'm tiring to do here) but I feel the learning experience is worth the time. To be honest i'm interested to see whats going to happen to the handling. If it completely sucks, I'll cross that bridge when I get there.
 

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Discussion Starter · #14 ·
Thanks for the kind words everyone, The hub should be in this week and i'll be able to get started on mounting the caliper this weekend.
I'll update soon!
 

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Ovaries on the Outside
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Freshjive said:
For welding of the disk brake tabs or bracket, I work at a welding shop where we do custom things like this from time to time. I feel that brazing the tabs on might be a better idea. I'm not sure how strong brazing would be for the tabs, but that's something i'll discuss with the welders. I have a micro TIG welder that can get down to the lower amps to ensure we don't blow through the piping.
Also ask the welders how they would reinforce the brake side of the rear triangle. It would suck to slam on the brakes and crush a seatstay.

Freshjive said:
For the rear hub spacing I plan to spread the rear triangle as you said. To cut down on any torsion twisting or unequal bending it plan to use and expanding clamp. Similar to the one pictured below. Maybe it's a good idea to heat the chain/seat stay before bending?
I only know much as I've read here. It is a fairly easy process that should allow for a somewhat exact spreading of the frame. He even has a good/cheap way to make sure the alignment is still good.

Freshjive said:
As for the geometry and handling, I think you got me. I'm defiantly going to be raising the center of gravity of the bike witch will have a negative affect of the handling. I wighted out the options of getting a better frame (one designed for what i'm tiring to do here) but I feel the learning experience is worth the time. To be honest i'm interested to see whats going to happen to the handling. If it completely sucks, I'll cross that bridge when I get there.
The high BB is something you will survive easier than the rake (potentially). Most cross forks have about 45mm of rake, which will probably be less rake than the stock fork. That will help with the "road" handling. Make sure the a-c length is the same or shorter so you don't get a lazier HA.

Good luck. This type of undertaking is the best for learning about bikes.
 

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weirdo
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6,223 Posts
Freshjive said:
Maybe it's a good idea to heat the chain/seat stay before bending?
No, much better to do it cold. I was going to add the Sheldon Brown link that Umarth just gave you, but no need to put that in again. I followed Sheldon`s method a few years ago when I spread the drops on my Schwinn commuter from 126 to 135- piece of cake. If you`re anal about it, you could even take the frame to a good LBS after spreading to have them check and dial in the alignment. I just did it by string and tweaked the dropout plates with a Crescent wrench as close as I could eyeball.

Also, it`s probably better to check with frame builders (either here or on other forums) about the details of adding disc tabs. Not to slam your welders, but personally, I`d ask people who have experience in exactly the matter at hand and for the application you`re looking at.
 

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Discussion Starter · #17 ·
I stretched the rear drop outs last night. I used a 9/16th threaded rod and screwed two nuts outward to get the stays to separate. The Chromoly steel had quite a bit of flex into it, I had to bend the stays out to 165MM just to get the extra 5MM I needed to go from 130 to 135MM

Test fit using my other mountain bike rim to ensure that a 160MM disk would fit without rubbing the chain stays.



The Alfine handspun wheel came it yesterday, It was packaged nice and neat everything showed up fast. After you buy the Alfine hub you need to buy the small parts kit from Shimano. The kit includes a locking ring to hold on the cog, the rear shift indexing assembly and 2 sets of non turn washers. The washers have a small tab the slips into the rear drop out slots to stop the hubs center shaft from spinning. Unfortunately the two sets of washers included in the kit are not designed for older bikes with a high rear drop angle (35 degress plus) to get these you have to spend another 10 bucks on washers. (kind of a money grab really). I also got the rear tire i'll be running it's a 35C kinda small block 8. The tire fits quite well.





Thanks
 

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ride the moment
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I stick a 135mm hub into 130mm dropouts on my SS commuter. I just push them apart and slide the wheel in and I'm good to go. My $0.02 would have been to get a Nexus IGH with built in roller brake and skip the welding. I know a local racer/mechanic who runs a Nexus around town. He's got the legs to break it and he's been on it for years with no problems. In any case good luck with the welding and such.

edited for spelling
 

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weirdo
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Freshjive said:
The kit includes a locking ring to hold on the cog, the rear shift indexing assembly and 2 sets of non turn washers. The washers have a small tab the slips into the rear drop out slots to stop the hubs center shaft from spinning. Unfortunately the two sets of washers included in the kit are not designed for older bikes with a high rear drop angle (35 degress plus) to get these you have to spend another 10 bucks on washers. (kind of a money grab really).
It does sound like a money grab. I bought a Nexus hub a few years back and it came with everything but the shifter. Along with those non-turn "washers" in several angles, it even had a pair of sprockets to choose between- 18t and 21t, IIRC. I can`t believe Alfine doesn`t ship with even one sprocket and a lockring.
 

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weirdo
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Dogbrain said:
I stick a 135mm hub into 130mm dropouts on my SS commuter.
Yeah, I imagine that would work pretty well too. I can`t say from first hand knowledge, but I`ve read that when the "standard" road spacing went from 120 to 126 and from 126 to 130, a lot of hubs came with beveled locknuts to make it easier to force them into the dropouts without respacing. Since my commuter had to go from 126 to 135, I went ahead and respaced- would have probably been a bit of a hassle to stretch that far every time I mounted the rear wheel. Then again, maybe not since I never tried to.
 
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