One of my things i do is go to the flee market and buy bikes in the same size for parts some times .
(MBBO-IV, Class 1) Deutsch Muscle Fahrrad
- Thread starter roadwarrior
- Start date
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I had to work this morning for a few hours but got home and tackled cutting the fork drop outs. I used a jig saw and cut them out. Bolted them together and drilled out the strut bolt hole to insure both sides were identical. Keeping them bolted together I shaped them with a couple of files. Very much improved front end. It pushed the wheel out 3 inches so my feet don't hit the tire when turning. The height was only increased by 1/4 inch. You can notice the difference it the last 2 pictures.
BEFORE...
AFTER
BEFORE...
AFTER
Forks look good!
Luke.
Luke.
These fork extensions seem to work well with the bolt set up of a springer fork. What does it do to the compression / rebound action of the fork? Dive at all in the corners? I definitely like the laid-out look of it on your build! I would have to incorporate something like this for me on a >26" sized wheel bike...food for thought....
Well the action of the springer still works fine. I haven't road tested it yet to see how well it works... still in the mock up stage.
The issue now is that I want to go from this tiny 32t chain ring to a 39t. Looking on EBay I can find nothing like this or anything to convert...
The cups are 40mm and the BB installs just like an American 1 piece crank. No threaded cups they press in. SO, I am stumped as to what to do without major modification. The chain ring that is on it is machine pressed on. Luke suggested grinding it off and welding in the chain ring... I am not a big fan of that considering that I would have to $$ someone to do it.
The cups are 40mm and the BB installs just like an American 1 piece crank. No threaded cups they press in. SO, I am stumped as to what to do without major modification. The chain ring that is on it is machine pressed on. Luke suggested grinding it off and welding in the chain ring... I am not a big fan of that considering that I would have to $$ someone to do it.
Is the bottom bracket the same size as a American? It might be the same size as a mid if it is a bit smaller, some kids 20" and 16" bikes run a one piece mid size BB...
If you can get an accurate inside diameter measurement, I am sure someone can help with what else may work...
Luke.
If you can get an accurate inside diameter measurement, I am sure someone can help with what else may work...
Luke.
Looks tuff man!!
Sent from my SAMSUNG-SM-N900A using Tapatalk
Sent from my SAMSUNG-SM-N900A using Tapatalk
Can you provide a photo of the bottom bracket shell with the cups that are installed, give me a better picture to reference in helping to solve. Maybe if you can, the I.D. of the actual BB shell (frame portion) to see what is available for adapter or other....The issue now is that I want to go from this tiny 32t chain ring to a 39t. Looking on EBay I can find nothing like this or anything to convert...
The cups are 40mm and the BB installs just like an American 1 piece crank. No threaded cups they press in. SO, I am stumped as to what to do without major modification. The chain ring that is on it is machine pressed on. Luke suggested grinding it off and welding in the chain ring... I am not a big fan of that considering that I would have to $$ someone to do it.
Ok, here you go. The opening is 40mm and it is non-threaded, just like an old school American bike... set the cup in and smack with a rubber mallet. The crank shaft is 16mm. The shaft itself is 127mm in length.
This would be a fairly reasonable fix. This BB set up with the adapter and bearings and spindle included. Found some online for ~$16.
http://www.jbi.bike/web/checking_product_description.php?part_number=22147
http://www.niagaracycle.com/categories/pyramid-m-x-3-piece-bottom-bracket-set-conversion-kit
Then right and left crank and a 39t chain ring to finish it off. See my PM.
http://www.jbi.bike/web/checking_product_description.php?part_number=22147
http://www.niagaracycle.com/categories/pyramid-m-x-3-piece-bottom-bracket-set-conversion-kit
Then right and left crank and a 39t chain ring to finish it off. See my PM.
Both of those are too large for this frame. 68mm is standard American sized BB. The ones I need are 40mm.
Okay, I see your post now that the ID of the shell is 40 mm. That will take more research. Give me 24 hrs. This has to be able to be solved.
Can't you retain the BB/spindle, and replace the arms/sprocket with other cottered cranks?
May be of some help:
http://sheldonbrown.com/cribsheet-unthreaded-bottombrackets.html
Could possibly be a Thompson?
The mid size BMX set up is 41mm, any chance you could make one fit?
Luke.
http://sheldonbrown.com/cribsheet-unthreaded-bottombrackets.html
Could possibly be a Thompson?
The mid size BMX set up is 41mm, any chance you could make one fit?
Luke.
I checked out some bikes in the pile today, as I remembered there were some kids bikes with smaller than standard bottom brackets, but still one piece cranks, turned out there were 3 of them, a 12.5" a 16" and a 20".
A quick disassemble on one and this is what I got:
Pretty much spot on 43mm. I know that is bigger than yours, but I wonder if you could combine your cups and bearings with these smaller one piece crank inner races and fit a one piece set up to it?
Luke.
A quick disassemble on one and this is what I got:
Pretty much spot on 43mm. I know that is bigger than yours, but I wonder if you could combine your cups and bearings with these smaller one piece crank inner races and fit a one piece set up to it?
Luke.
I found what I needed! Fresh from China! Well they will get here in a few weeks anyway. The chain ring is at the bottom of what I wanted. I was looking for a 39t but 36t will work.
Glad you came up with a solution!
Luke.
Luke.
Good find! This should fit the bill nicely. Let's hope they are not on a "slow boat from China".....
