OMS Ironhead Thumper : 02

Have you ever put together a 3 dimensional puzzle? Well this is what we have here. My plan at this point for the “Half A Harley” is to assemble everything as intended from the factory, then do the fab work for the custom bits and finally pull the motor and make it from a v-twin to a thumper single.

The bike arrived at my shop in a few totes. I separated out what I know fits and where it goes. As with every puzzle you need to start somewhere. I start with first the easy large things that I know where they belong and hopefully everything else will fall into place as the boxes get emptier.

One of the biggest hurdles is locating all the fastening hardware as I go. I have a very good selection of used bolts and fasteners from other projects that I have done over the years. I will be mining for the correct hardware in the various boxes and totes that I have acquired. As you may know most shops have a miscellaneous bolt box around to catch all the cast offs when the project is complete.

So far we have rebuilt the swing arm pivot and installed the vintage spring struts out back, then added the dual disc front end taken off my last project. I am saving The Performance Machine calipers and the mounting brackets that were included with this bike for another project or if needed to sell off to keep my budget below the $1000.00 max limit. The motor is installed in the frame and the front brakes are plumbed and bled using a combination of used custom vintage steel braided lines and stock Harley rubber brake lines. It is not the prettiest set up but it is cheap and works.

Next on the list is to get the disc brake rear wheel and caliper mounted up and on location. This bike is supposed to have a mechanical drum rear brake with a 5/8” Axle diameter. I am installing hydraulic disc brakes with a ¾” diameter axle so some machining is in order to get the whole deal to work together.

Tim

OMS kz440 superbike : 10

Need to up the secondary mains a bit, figure out a seat, and some other gibberish. Just about road legal to start raping the streets.

Derrick

OMS kz440 superbike : 09

Got a lot done in the past month or so. I really wasn't digging the bottom mount Bates style headlight on this bike. It looked out of place, and the bracket I made was just janky. I really liked the stock unit, so I chopped down some old universal brackets to weld onto the fork covers I previously made. Super tight fit, but it looks much better. Added some fork gaiters that still need some trimming, but we are inching closer. Also got in a new master cylinder since the stocker was shot. I saved some much needed cash on the budget by keeping the stock headlight, caliper, and brake line.







Things weren't progressing quick enough for me, so I took a full vacation day off work to get out in the garage and get the 440 going. I did the following:

carb diaphragms
set float height
blow out jets and openings in carbs
install all new carb o-rings
make new pilot screw washers(missing)
install petcock
fuel lines trimmed and quick disconnect on tank for fuel crossover
oil uni-filters
handlebars trimmed
handlebar grips trimmed
front brake bled
throttle assembly setup/adjusting
throttle cable routing/adjusting
clutch cable routing/adjusting
wire/install new coil/plug caps
install new regulator rectifier
install chain/adjust tension
adjust and clearance rear brake pedal/linkage
finish wiring everything but the lights
adjust points/timing
fork fluid
tighten up exhaust





I didn't think to have a battery fully charged and ready to go, so instead of hearing a beautiful roar, I got to hear the starter chug a couple times and that was it. After some trickle charging, I finally got to hear it run. Shitty. I spent about a week chasing down little issues here and there. Once I got it to idle, mid throttle it would just cackle an cut out instead of rev. Found out the points/condenser were trashed, and now it revs to the moon with ease. I have a slight, and I do mean slight, hesitation at idle. Here's a video of one of the first rides when the points were bad.



Still tuning for the most part, but now I can focus on making a seat pan, inner rear fender, chain guard, front fender, and sealing some oil leaks on the side covers.

Derrick

OMS Ironhead Thumper : 01

So I decided to throw my hat in to the ring for another Ozark Mountain Scramble. I deal in American bikes and parts on a daily basis so I thought it would be a good idea to utilize my knowledge or interchangeability and a part stash from other projects that I have done.

We will be building a 1975 Harley Davidson Sportster. You say foul! Harleys cost too much and are too large for the displacement rule! As you may know the Ironhead Sportster is at the bottom of the food chain as far as American V-twins are concerned. They can be acquired for a song running and if you do a little wheeling and dealing you can get a basket case bike on the cheap.

Have you ever heard the term for a Sportster as “Half A Harley”? Well that is what we plan on doing to get the bike to fit the 750cc displacement rule. The 1975 Ironhead Sportster motor is a unitized construction V-Twin with cast Iron cylinders and cast Iron heads hence the term “Ironhead”. We thought that we would cut down on the bore by sleeving the cylinders and new pistons. This would make it a 750cc V-twin. The more I thought about it nobody would believe me that I really did the work as there would not be a good way to check the motor to make sure I was not telling a tall tale. So, the plan is to take this V-Twin and turn it into a Thumper Single! I have a few ideas on how to go about this. We will be posting pics as the progress unfolds over the next few months.

Tim

OMS moto guzzi : 04

Couldn't wait for daylight or a seat. The Guzzi is back on the road.

BG Uno

OMS cl360 : 04

Finally buttoned up the CL motor, so progress is starting to happen now. Had to cut down an aftermarket cam chain to fit, so there were a few minutes of head scratching to figure out the what, where, and how of that. I managed to take that op to snap a shot of the motor mid assembly.



While I was waiting for engine parts, I finished reassembling the rest of the bike. I was lucky enough to have an extra low mile 18" x 4" tire laying around, so I mounted it up with a new tube and strip. I also snagged a low buck seat on Ebay. Rolling around the yard and seeing it look like something got my motivation up a bit.



I decided to go simple and hit the motor with a quick coat of high temp silver just to keep things clean.



As soon as the paint was dry I wrestled the motor in the frame and mocked up the exhaust.



I was dying to fire it up last weekend, but the points advancer was toast and I had to wait for a replacement. It came in this week, so I got the carbs on and points in and set Friday, and she fired up yesterday. I still need to rebuild the petcock, replace the front tire and some cables, and pick up a drive chain. She's pretty close now though.

Andy