News and Events

Keep up to date with the latest news and events of Modular Bikes.

Wednesday, June 22, 2011

Building a new Bike Part 1

Hi After a break of a year or two, I have started building a new bike. (If you've got my book, "an Illustrated guide to the cycle zoo", then the build process is for one of the bikes shown in the on-line "long wheelbase plans"). And , truth be known, it won't be all that different from the last one (big at the front) I built but I am including a Schlumpf Mountain drive in the bike this time. When I last ordered laser cut parts for one of these bikes, I ordered 3 sets, so it's just a matter of pulling some of these parts from the shed.

A friend rang up and said he had some old bike bits he was chucking out and I could grab them if I wanted. There were 700c wheels, a frame, some pedals, lots of cantilever brake bits and they're a good set of parts. At about the same time, I contacted Greenspeed about buying in a Schlumpf mountain drive. This is a gearbox that has the form of a standard crankset but includes a standard 1:1 drive and a 2.5x reduction gear. After about two weeks, several emails and a few phonecalls and a considerable lightening of the cheque book the parts arrived. So that's most of the bits needed to start.

First step in making the bike was to remove the steerer tube from the donor frame. Although this frame was quite nice, show no mercy is the motto and after removing the fork, I ripped into it with a pipe cutter, hacksaw and angle grinder. Next is bending the front fork, the forks must be widened to fit a back wheel.

At this stage, I put the front wheel, fork, and steerer tube into the main frame. This is to check how the clearances for the crankset will be. I decide that the v-brakes I try out are a bit big (aim is to have the frame fairly low on the steerer) and decide that mini v's would be the go. A couple of local bike shops don't have any, so I order 2 sets through . Hopefully they will arrive soon!

Yesterday, I put a small chamfer on boltholes of one of the schlumpf trouser guards (I will have one ring each side of the 42t chainring) so the bolt head will stay central in the hole. This evening I put the chainring and trouser guards onto the Schlumpf and lastly for this post, work out the gear inches for the bike. Lets say I get an 11-32 teeth cluster.

Top is 105", lowest is 14.5", range is 730%. I have been getting round with a 7 speed for qite a while now, the schlumpf should make things much easier.

All for now.

Steve Nurse

No comments:

Post a Comment