Author Topic: Hondaman Special #1 hits the road! (Read 5138 times)

HondaMan · « **on:** July 23, 2009, 09:30:26 PM »

Today, one of our members came and rode away with the rebuilt Hondaman Special #1, a 12/72 original build of a mid-year 1973 CB750K3. I started with a junkyard refugee, and because of the help from MANY of you, rounding up pieces and parts, it buzzed away today with a happy new owner (Aha! We've infected another rider!)

My heartfelt thanks to all of you (and you all know who you are: there were 17 contributors to this bike, in one form or another)!

Non-stock items include a modified clutch hub for smoother engagement and cooler running, ported head, deshrouded and polished valves, trimmed swirl ridges in the combustion chambers, and balanced piston-rod-wristpin-ring sets, with new rings (3-piece oil control rings). It sports a 17T front sprocket, for sneaking up on local HD and unsuspecting sportbike riders, Avon feet, lowered suspension and a lengthened wheelbase.

Before & after:

scunny · « **Reply #1 on:** July 23, 2009, 09:40:11 PM »

nice work. hope the lucky new owner enjoys it

mystic_1 · « **Reply #2 on:** July 23, 2009, 09:42:20 PM »

Sweet!

Carry on, Dr Frankenstein!

mystic_1

GammaFlat · « **Reply #3 on:** July 23, 2009, 10:00:49 PM »

That bike looks awesome - same one from the now-famous video! Yahoo! Great job!

More, we want more!

Regards,

John

voxonda · « **Reply #4 on:** July 23, 2009, 11:23:36 PM »

That is one great looking bike, Mark! Congrats!
Can you fill us in about the smoother engagement and cooler running of the clutch?

Regards, Rob

Bob Wessner · « **Reply #5 on:** July 24, 2009, 05:07:57 AM »

Lucky bike, lucky new owner.

Very nice work, Mark.

MCRider · « **Reply #6 on:** July 24, 2009, 06:07:44 AM »

Quote from: voxonda on July 23, 2009, 11:23:36 PM

That is one great looking bike, Mark! Congrats!
Can you fill us in about the smoother engagement and cooler running of the clutch?

Regards, Rob

Ditto what he said.

captaincrash80 · « **Reply #7 on:** July 24, 2009, 07:04:18 AM »

I want one

manjisann · « **Reply #8 on:** July 24, 2009, 07:08:08 AM »

VERY NICE!! Always good to see another honda saved from the scrappers.

Brandon

lynchj · « **Reply #9 on:** July 24, 2009, 09:11:22 AM »

Beautiful job Mark. Are you taking orders for more?

HondaMan · « **Reply #10 on:** July 24, 2009, 09:20:50 AM »

Quote from: voxonda on July 23, 2009, 11:23:36 PM

That is one great looking bike, Mark! Congrats!
Can you fill us in about the smoother engagement and cooler running of the clutch?

Regards, Rob

This little fix hearkens back to an old post (several, actually) about improving the clutch on the 750. Here's the first link, which Steve put into the "Thoughts" post long ago:
http://forums.sohc4.net/index.php?topic=7401.15

You can add about 4 extra oil holes in the recessed portions of the hub's splines (where the plates' teeth won't push against them), or you can increase the oil capture of the existing holes by cutting "catch grooves" into the existing middle holes, and then lower the edges of the holes that are in the back corners of the sections of the hub. Pix below may help the explanation. The little grooves that you see in these pix are deeper at the holes than at their beginning edge: the idea is to capture more of the oil that is sliding across the face of the inner hub surface.

It will typically take about 15-20 miles of riding to initially increase the oil in the clutch pack, but after that it will stay wetter and run cooler.

voxonda · « **Reply #11 on:** July 24, 2009, 09:28:15 AM »

Thanks Hondaman,

Thanks also for the link, nice to read all that!

Regards, Rob

HondaMan · « **Reply #12 on:** July 24, 2009, 09:29:27 AM »

Quote from: lynchj on July 24, 2009, 09:11:22 AM

Beautiful job Mark. Are you taking orders for more?

Actually, yes...
I started on HS#2 for a rider from Omaha, who wanted it to be a Dunstall-seat-and-tank body, but haven't heard from him in quite some time. I suspect he may be like lots of us, out of work... $:-\$

This one is a late K3, was probably sold as a K4 originally. I'm titling it as a K3, though. Inside, it will get the same treatment as the last one, except possibly a bore job to an oversize because I'm none too happy with the rust levels I see in my current crop of cylinders. Not to worry: I have 4 sets, and all are getting bored to some size or another! It would be terrible to have to put up with the extra HP this will generate...

Right now, I have the engine (I'm in the rebuild phase of it at the moment), rolling frame, Continental tires (with 8 miles on the front one), rear fender(s), taillight and all electrical equipment. I need a front fender, though. I'll be getting some new rear brake shoes for it, and am searching for a non-squeak front brake puck set. Then it's just rounding up all the nuts, bolts, and screws that are surely missing from this kitbashed collection of K2-K3-K4 basket case parts I started with. At least, the engine was whole, just non-running, when I got it.

Ecosse · « **Reply #13 on:** July 24, 2009, 11:33:40 AM »

nice job hm! a poor decrepit sohc could fare worse than to be in your hands.

so, just out of pure curiosity, is your intention to build to suit or are these to have your basic improvements plus whatever the customer wants? i think you may have touched on this in the past, yes?

bwaller · « **Reply #14 on:** July 24, 2009, 02:37:06 PM »

Well done Mark, it's good to see another one revived.

GammaFlat · « **Reply #15 on:** July 24, 2009, 05:11:18 PM »

Hey HondaMan, are the clutch pictures a preview of the upcoming book?

HondaMan · « **Reply #16 on:** July 24, 2009, 05:20:09 PM »

Quote from: GammaFlat on July 24, 2009, 05:11:18 PM

Hey HondaMan, are the clutch pictures a preview of the upcoming book?

Yep.

HondaMan · « **Reply #17 on:** July 24, 2009, 05:25:52 PM »

Quote from: Ecosse on July 24, 2009, 11:33:40 AM

nice job hm! a poor decrepit sohc could fare worse than to be in your hands.

so, just out of pure curiosity, is your intention to build to suit or are these to have your basic improvements plus whatever the customer wants? i think you may have touched on this in the past, yes?

Well, it starts out with my 'basic engine mods', so i can give it a meaningful warranty. Beyond that, the rest of the bike starts out to be stock, unless the [prospective] customer has a special request. In the last one's case, there was need to lower it somewhat, so it got different shocks and a longer wheelbase while slipping the forks up a little, so it won't get 'choppy' in city riding. The steering head gets real bearings and the swingarm gets my treatment, too. It seems almost everyone has their tire taste: I just happen to have these Continentals left from the once-prospective owner's request (he disappeared). The new owner desired Avons on HS#1, so I swapped them out for HS#2.

Ecosse · « **Reply #18 on:** July 24, 2009, 10:47:36 PM »

hold on... back up, book? i'm committed to one as of now!

oh, thanks for the explanation. ever any long term plans for non 750 sohc's?

HondaMan · « **Reply #19 on:** July 25, 2009, 07:16:48 AM »

Quote from: Ecosse on July 24, 2009, 10:47:36 PM

hold on... back up, book? i'm committed to one as of now!

oh, thanks for the explanation. ever any long term plans for non 750 sohc's?

Well, I think I'd come off like a dunce on anything else (except maybe the 450 twins). I worked so much on the 350T/450/750/500 bikes that I ended up memorizing them, in those days, and all the notes I ever kept applied to those bikes.

I think that if I had $1 for every 750 I touched from 1969 to 1980 I could pay off my mortgage...

Ecosse · « **Reply #20 on:** July 25, 2009, 02:23:02 PM »

Quote from: HondaMan on July 25, 2009, 07:16:48 AM

Quote from: Ecosse on July 24, 2009, 10:47:36 PM
hold on... back up, book? i'm committed to one as of now!

oh, thanks for the explanation. ever any long term plans for non 750 sohc's?

Well, I think I'd come off like a dunce on anything else (except maybe the 450 twins). I worked so much on the 350T/450/750/500 bikes that I ended up memorizing them, in those days, and all the notes I ever kept applied to those bikes.

I think that if I had $1 for every 750 I touched from 1969 to 1980 I could pay off my mortgage...

well... "jack of all trades, master of none" often rings true; so, you're a 750 guy.

of course, it's all relative as your 'dunce' is my aspiration.

News:

Author Topic: Hondaman Special #1 hits the road! (Read 5138 times)