It was a 1982 or '83 YZ250 front end on my XL175 Honda. The front brakes as I recall (vaguely) were excellent for the build purpose of the bike (enduro/hare scrambles).

I said the hub in question was a Honda, but my Honda (XL 175). It had a Yamaha YZ front end on it. I think that is what your friend has on his bike, Victor.

You will appreciate the reeds in the woods for sure. Low end torque-age is a must for low speed grunt, quick, controllable acceleration on a tight single-track woods course and hill climbing.

Looks like Honda. Front end too.

I would suggest some suspension upgrades. At least rear shocks and a front fork brace are advisable if the type of racing you are considering has any gnarly terrain or jumps. Beyond that, in my opinion, conversion to reed induction pays great dividends in either discipline, although you need to cons...

I don't know about the Powerdynamo ignitions, but the PVL ignitions I run on my race bikes do not have the provisions for running lights.

On the same theme, is the fork seal supposed to seat all the way against the stop in the seal nut? I whanged on it with a seal driver with about as much granuch as I felt prudent but couldn't get it to bottom out. Of note, they are now roughly at the same depth as their predecessors were. They are t...

In that case, check with the upholstery shops in your area.

Quess - to keep the hub from binding/wearing.

...and that's one of my very favorite parts of the whole schmeer. A company that made up it's own rules, lived by them, and succeeded. A quaintly precious notion from the perspective of the current cluster. Every so often, I let my mind ponder the possibilities if Hodaka were to have said to themsel...

Dig

Groovie. As thorough as the rebuild is per your description, I would have been surprised if anything beyond a bit of tweaking here and there wouldn't solve the problem. Great news.

Air is good. Spark is good. So its back to fuel (assuming compression is good). Crazo-detail carburetor eval? Chase all passages with copper wire, etc. In-line fuel filter, yes? Was the engine leak-tested after reassembly?

A few quick questions: 1) Was the engine well warmed up prior to the "speed trials"? 2) What spark plug are you using? 3) Proper gap? 4) Have you tried swapping for a brand new plug?, and 5) what does the firing end of the plug look like? Every so often, you can get a bogus plug. Also migh...

That's a positive (failed) leak-down test. It should hold 6 psi - ideally forever. Time to chase down the leak (including your leak-down test kit and connections). You'll need to change those 43 year-old seals anyway, but finding a leak elsewhere can direct your attention to that area when you overh...

Holy crap, Captain. Ounces...pints?? Maybe I need to slow down so I can go faster . Nice annotated pictures, by the way. That should really help.

Sorry Captain, that should read "Slide height" adjustment screw.

I just took a closer look at the photo of your clutch cover. It looks like someone replaced your oil fill cap/dipstick with a magnetic bolt (probably a drain plug from another bike). Anyway, that is where you will replenish the oil.

What you have indicated with the arrow is the crank case breather. The oil fill port is on the clutch cover. There will be a white plastic cap with a built-in dipstick indicating the correct fill hole. The first picture you posted on this thread shows the clutch cover where the oil fill hole is loca...

Correct generally. You don't need to remove the magneto cover to change the oil and the oil fill hole is on the clutch (right side )cover. If oil is accumulating in the mag cover, you have a leaking mag side crank shaft oil seal. If you completely drain all oil from the machine (crank case and clutc...

Yep, no cover on the Ace 90. Just a (tidy, secure, well-organized) lump of wires.

The clutch (right) side cover is filled with the same oil that lubricates the transmission so when it is removed, several ounces of oil are released. That is normal. If you are seeing oil drain when removing the magneto (left) side cover, you have a leaking crankshaft seal. That's ok. All seals shou...

Have you maxed out the tweaking possibilities of the float height (idle adjustment) screw on the left side of the carburetor. The brass one with the visible spring.

Your photos depict the clutch and magneto covers - not crankcase halves. Incidentally, you have your right and left labels reversed. The drain plug is as shown on the right crankcase half. Its great to see you digging into that insanely cool bike. Good help every step of the way here on this forum. ...

Get one of each next time you're by an Ace Hardware and you'll get change back from a quarter. The good thing about investing in good tools is that they'll last a lifetime and you'll use them again and again.