First build thread... '47 Knucklehead basket case

[JakeF]

All the wiring was complete junk, with insulation cracking and falling off and dumbass crimp on connectors everywhere.

[Tattooo]

It was in really rough shape. I hooked the cable up to it and couldn't get it to turn at all. Trip odometer reset wouldn't turn either. Worth the price to me to have it gone through![ATTACH=CONFIG]97337[/ATTACH][ATTACH=CONFIG]97338[/ATTACH]

Do not repaint the face or the needle just clean it........ Just redo the odometer and numbers...........

[JakeF]

Pulled the heads and jugs last night. Cylinder walls look great to me, pistons I think will be fine with some clean-up,,, just cruddy with carbon on top.

Looks like it's been bored out a bit. I'm measuring 3.4260 and my manual says stock bore is 3 5/16" (3.3125)... seems an odd measurement. I would have expected an even .10 or .20 over, but this is .1135 over stock if my measurement is accurate. The pistons themselves measure 3.4110".

I'm debating about trying to do the heads myself or bringing them to a local shop... I haven't done valves since I rebuilt a Ford flathead V8 when I was 14, and that was almost 30 years ago.

[Tattooo]

You can't check the cylinder at the top. Well you can but it won't be accurate......

But the rest of it looks nice for it's age.

If it was me I would clean everything up, Inspect then lap the valves if they look ok. Clean the cylinder walls with a dingle berry hone. Install new rings and put it back together.........

But I'm cheap and I've done it many times on cars and bikes....... I've NEVER had any problems.....


How does the bottom end feel????????

[JakeF]

OK. I'll measure the bore again tonight at the bottom end of the jug. Just want to make sure I order the right rings!! I have a stone cylinder hone, but not a dingleberry hone. Is there a benefit to using a dingleberry hone instead?

I haven't looked very closely at the bottom end yet, but rods felt tight and flywheel spins smoothly. Anything in particular I should look for? Hoping I don't need to split the case apart, but I do have a new gasket for that in the event that is necessary.

[Tattooo]

I have a stone cylinder hone, but not a dingleberry hone. Is there a benefit to using a dingleberry hone instead?

You need to measure it in the middle also......

Which hone to use matters on what your trying to accomplish...... If your just wanting to get the shine off and cross hatch the cylinder use a dindleberry hone.....

[Tattooo]

Hoping I don't need to split the case apart, but I do have a new gasket for that in the event that is necessary.

Do it anyway it's easy as hell....... That way you can clean the inside and reseal the case............ Now you don't want to take the flywheels apart unless you find a problem............

[Tattooo]

By the way you did say you have a manual didn't you??????????

[JakeF]

You need to measure it in the middle also......

Which hone to use matters on what your trying to accomplish...... If your just wanting to get the shine off and cross hatch the cylinder use a dingleberry hone.....

OK. Is 240 grit good for this? I'm seeing 120, 180, 240, 320, 600, and 800 available.

Thanks for your input, by the way! Much appreciated!!

[JakeF]

By the way you did say you have a manual didn't you??????????

Yes, I found a scanned PDF of the service manual. The photos didn't scan very clearly, but all the text is legible.

[babysfirstbike86]

Ah, I remember when I got my first big project... those were the days!


Man that is going to be awesome. Excited to see what you do. And I love it in the living room- what lamp or ottoman is cooler?

[Tattooo]

Yes, I found a scanned PDF of the service manual. The photos didn't scan very clearly, but all the text is legible.

Do yourself a favor and buy several different PAPER manuals and a parts manual.......... A PDF is for cheap people that aren't really interested in working on there bike for years to come...................

[JBinNC]

For accurate measurement of the pistons and cylinder bores, a micrometer and suitable telescope gauge, or even better, a dial bore gauge set with the micrometer used, are necessary. The digital caliper pictured is good for a lot of things, but piston and cylinder fitting is not one of them.

By your own figures, the 3.4110 piston would be plus .100, not unusual. However, with a bore of 3.4260, again your measurement, you have a .015 skirt clearance, which is WAY bigger than it should be. If your measurements prove to be accurate, just honing and reringing this motor will avail you nothing. You need to have the cylinders bored and honed for a larger piston, if one is available, or the cylinders and pistons need to be replaced.

Don't build junk, and you won't have junk when you are done.

Jim

[Tattooo]

If your measurements prove to be accurate, just honing and reringing this motor will avail you nothing.
Jim

Yep that's why I said to check them accurately before you make your decision...........

[Tattooo]

Don't build junk, and you won't have junk when you are done.

Jim

I totally disagree,,,,,,,, This bike was built from a bunch of this and that junk parts............. I spent only 4K building it in 2008........

It's more about knowing what to do with junk parts......

Yes you can throw a bunch of money at something and it should turn out really nice but not always.....