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KenVW
09-13-2012, 11:33 AM
I'm just starting on the streetfox. I have about 6 doner bikes. 2 are swing arm MTN bikes. from the plans I see the bottom bb stays with the rear suspension and is not used. another one then is used up front for the crank. Problem is the diameter of the BB on my 2 suspension bikes are smaller than all the other bikes I have, even a little kiddie bike. I purchased a mongoose full suspension MTN bike with 21sp shimano to get all the drive stuff from. Havent taken it apart yet but I'm sure the crank/bearings etc from the new bike won't fit the larger diameter BB's which seem more common. I do have another MTN bike with a 3 chainring setup but would rather use the new stuff :confused:

Considering cutting the BB out of the suspension triangle & replacing it with a filler/bracket of some sort & would have to incorperate the pivot here also since I would have cut it off too. too much work? easier way? I don't want to scrap the supension on the 2nd bike cause it's hopefully my next trike. :builder2:

I'm also considering a build thread as I will have bunches of questions I'm sure. Where would/should that be started if I do?
Ken

bns1969
09-13-2012, 06:10 PM
I had much the same questions recently when I made mine. Try to find a BB from a bike that has at least a 3 piece crank it will have 2 pedal arms and a conector axle with the square ends. Those seem to have a much easier to find bearing set for later repair. If all you have are large 1 peice cranks on the other donors you might look around for a newer mountain bike off like Craigslist for under $50 that has a 3 piece crank. Its not nesasary but it will allow you to change the length of the pedal arm to suit your comfort later and most higher end cheap bikes will have aluminum arms to keep your weight down as well. All thats just my oppinion but I wouldn't sacrifice a suspension arm that has the crank attached to it just yet because you will want to build another bike later! Its not really important which style crank to use but it seems that all of my donors had either a large 1 piece crank or the smaller 3 peice units and they did interchange big for big and small for small. Use the whole new bike (probably from Walmart I bet) for all the brake levers, cables, derailers and so on, that way the derailers will match the shifters for sure. Then take apart a few of the old bikes for the needed forks and head tubes. Try to keep each bikes parts together too! I had a hell of a time matching bearings to cups and races when all my parts where just in a pile! I would start with the massing of the parts needed to do the build from your donors first. Then follow the build instuctions you got as close as possible. Wheels are also VERY important! If your pile of parts resembled mine you my find that your short a useable BMX style wheel or 2!

As for the build thread I would love to see it and I think you would just start a new thread here and if its not right than the admin would just pop it in the right catagory.

Happy building I say!!!!

darnthedog
09-13-2012, 06:52 PM
Another option would be to just buy a new bottom shell rather than a whole bike. I got a couple through here:
www.cycle-frames.com/bicycle-frame-tubing for less than $10 and sold in any material you want many of the proper sizes. There are other suppliers I am sure. But it beats having to fill the holes or cutting up another bike. Just be sure to measure your original Bottom bracket to verify the size.

KenVW
09-13-2012, 08:49 PM
Thanks, that website just might do it! I'll need to disassemble & measure. I never dreamed you could buy frame pcs like that. I cut the head tubes from 2 bikes this evening, cleaned them up and got both forks cut clean & sawed to 1" lg. Still deciding on my front wheels:rolleyes4:. Got 3 quotes on steel today from work. $90-130. Finishing up an RC plane build, sprayed for spiders around the house, it's been a busy evening.

bns1969
09-13-2012, 11:14 PM
Not sure where you get your steel but a single 1 1/2" 14gauge stick about 12-14 feet in length is all you should need. Assuming you cut once and measure twice! I paid about $40 for what I needed but there is a bit of steel compitition in my area to keep the prices resonable.

KenVW
09-14-2012, 10:00 AM
ordering steel thru my workplace (machine shop) was going to get 1-1/2 sq/16ga x 12' & 1" sq/16 ga x 6'...but I found some 1" so now I only need the 1-1/2 sq!

Quick Question: 200 lb rider, gentle/sane riding on bike paths..16 ga or 14 ga.? would like to save the 3-1/2 lbs difference.

darnthedog
09-14-2012, 01:22 PM
ordering steel thru my workplace (machine shop) was going to get 1-1/2 sq/16ga x 12' & 1" sq/16 ga x 6'...but I found some 1" so now I only need the 1-1/2 sq!

Quick Question: 200 lb rider, gentle/sane riding on bike paths..16 ga or 14 ga.? would like to save the 3-1/2 lbs difference.

I Was 285 now roughly 240- I used 16 gauge on my Warrior Frame which is a rolling frame and it supports me just fine.
Local Steel Supplier here was $2.00 a foot and it comes in 20 foot lenghts- bought 40 foot and had them cut in two. Lots of projects came up and used up the first 20 foot really fast. So if you paying $90 to 120 you being ripped off. Shipping is horrible unless your buying by the tons weights.
Find a local steel supplier and pick it up. Fencing supplier also carry quanities of Square tubing.

bns1969
09-14-2012, 07:04 PM
ordering steel thru my workplace (machine shop) was going to get 1-1/2 sq/16ga x 12' & 1" sq/16 ga x 6'...but I found some 1" so now I only need the 1-1/2 sq!

Quick Question: 200 lb rider, gentle/sane riding on bike paths..16 ga or 14 ga.? would like to save the 3-1/2 lbs difference.

I think the 14ga to 16ga is debatible but cut your wieght other ways in my opinion. Heavier is safer. I was able to get away with 1/4" plate for my brake brakets welded to 3/4" square tube intead of the 1", I should have went with 3/16" but its what I already had. As short as those pieces are once thier welded the whole knuckle assembly ends up really solid. I've been thinking of trying to actually wiegh my whole bike completed but I can say its still light enough to load and unload in the back of my truck by myself and I had the LBS say it looks a lot hearier than it really is.

TexasTuff
09-14-2012, 08:21 PM
It's been a few months ago, but I bought 20 feet of 1.5" square tubing 16 gauge for $26.00 and they did one cut for me. That was in Garland, TX.

KenVW
09-14-2012, 10:36 PM
Yes, the steel companies are not doing our shop any favors. I called another steel company about an hour from me and they will sell me a 20 ft bar, I pick it up dip for 23.00. He said if they cut it to add another 32.00!! By the time i took a half day vacation & haul a trailer there i wouldnt be saving much. I also call a local welding shop & I can get a 20' bar there for 32.00 but all they have is 14 ga, no 16 ga. It only a short distance from where I work, convenient. I'm finding it's cheaper to get a whole bar than have it cut. I'll have to wait till next week now. This weekend I plan on disassembling the new mountain bike donor. Man I really appreciate the input, it's nice to have like minded folks to talk to.

David_s
09-15-2012, 03:56 AM
A battery powered sawz-all is a good investment.

darnthedog
09-15-2012, 08:23 AM
And if your in decent shape an old fashioned hack saw works great too- with a new metal cutting saw blade and some spares.

KenVW
09-17-2012, 07:24 AM
Are these the correct ones for my Walmart mongoose mtn bike?

Mine measured :

OD 1.56" / 39.6mm
iD. 1.332"/33.8mm @ the threads
length 2.664" / 67.7 mm

Looks like the one for $4.25 is the closest in diameter. All the rest are 38.1 OD I'm assuming the I'd and threads are somewhat standard?

Ticktock
09-17-2012, 10:51 AM
Easy way to weigh--just put each wheel inj turn on the bathroom scales, and add the figures!
Steve G

KenVW
09-17-2012, 01:35 PM
Think you my have posted on wrong thread ;) I'd still like a little confirmation before I order my BB Shell from these folks.
Ken

KenVW
09-17-2012, 04:06 PM
Let me try this again, I forgot the link. thats the kinda day im having.

Are these the correct ones for my Walmart mongoose mtn bike?

http://www.cycle-frames.com/bicycle-frame-tubing/STEEL-LUGLESS-SHELLS/


Mine measured :

OD 1.56" / 39.6mm
iD. 1.332"/33.8mm @ the threads
length 2.664" / 67.7 mm

Looks like the one for $4.25 is the closest in diameter. All the rest are 38.1 OD I'm assuming the I'd and threads are somewhat standard?

darnthedog
09-17-2012, 06:02 PM
Let me try this again, I forgot the link. thats the kinda day im having.

Are these the correct ones for my Walmart mongoose mtn bike?

http://www.cycle-frames.com/bicycle-frame-tubing/STEEL-LUGLESS-SHELLS/


Mine measured :

OD 1.56" / 39.6mm
iD. 1.332"/33.8mm @ the threads
length 2.664" / 67.7 mm

Looks like the one for $4.25 is the closest in diameter. All the rest are 38.1 OD I'm assuming the I'd and threads are somewhat standard?

I'll agree that that is about the closest BB. Part#: NOV_LLBB_STD_69

there may be a mm or 2 off on length but that probably will not be an issue. If nothing else you can take a flap disc and shorten it up a little bit.