Presidio High School Knucklehead Special

i don't know guys, a stock 6 volt battery is around 70 to 80 bucks last time i checked.

they last a long time. and when properly sized wire is used are just as bright as a 12 volt system. other than finding spare lamps i cannot see much advantage in going 12 volt.

my last 6 volt battery made it 10 years and failed only after i dropped it and cracked the case.

btw, both of the hardware stores within a mile of my home still stock 6 volt lamps for the dash, running and tail lamps in my bike. head lamps come from an independant bike shop about 2 miles from me. i cannot remember the last time i had to change out any of them.

john

Howdy John,

If I'd had a good 6 V generator I might have used it, but since I had to buy a generator anyway the 12 V Cycle Electric with built in regulator was the easiest way to go. Advantages of the 12 V system include smaller gauge wire, ability to use readily available (and BRIGHT) H4 headlight bulbs, LED 1157 tail light bulb replacements (no filaments to break, a consideration on a rigid frame bike ridden on rough roads), more easily found replacement bulbs and batteries. I've had to replace a blown tail light bulb at night from a convienence store, and they did NOT have any 6 V stuff. As well, when I had to replace this last battery, the local auto parts store had a small selection of 12 V motorcycle batteries but no 6 V on hand. But you're right, if a fellow has a working 6 V system there's no compelling reason to change, as you say, 6 V stuff is available and its no big trick to carry a set of extra bulbs for emergencies.

I ran a search for the Odyssey battery and came up with an outfit in California that sells them.
http://www.odysseybatteries.com
I think I'm going to look into it; I don't know how well the little dirt bike battery I'm running now is going to hold up, its smaller than the 12N5.5A-3B that is normally used in H-D 12 V conversions. The Odyssey site says that the PC 545 is a replacement for the Yuasa YB16-B, which is the battery my Victory uses. They are supposed to have a 2 year shelf life so I think I'll order one and have it on hand. One or the other of my two bikes will most likely need a battery within two years and it'd be nice if they were both set up for the same battery.

I'm getting ready to head into town for my summer school class; I have 15 boys, 10 in-coming freshmen learning to weld and 5 in-coming seniors overhauling a couple of ATV 4-wheelers. The class will finish next Wednesday and I'll have a good cadre who have a jump on things to start the 2008-2009 school year when we crank up again in August. I have a couple of iron-head Sportsters lined up for next year's projects and I'm looking forward to getting going with them. Thanks again for your interest and I'll keep y'all posted on how the PHS Knucklehead Special is working out.

--- Randall

Howdy Folks,

I put around 200 miles on the PHS Knuclehead Special on Saturday; still running the points. The bike ran great, no problems at all. It was unusually cool, with thunderstorms drifiting around the Big Bend, in the 80's F for the most part in the high country at 4,000 to 5,000 feet. Easy starting and running 65 to 75 mph for long stretches. Ran cool and strong, no oil leaks, missing or hesitation and folks everywhere I went agreed the bike was a thing of beauty. I love Knuckleheads! And a very good summer to you all!

--- Randall

I run the same as system as Brent except run a Yuasa YTZ14S along with the CE genie/reg on end,12v. The battery sits on end in stock oil bag....4yrs now and NO problemo.....

[Pa]

I've owned many products by Yuasa. Never had a problem with any of them. Yuasa produces various products. From automotive, motorcyle, machine tooling, I was. and am. very impressed by their quality. Pa

Howdy Folks,


I haven’t posted for awhile as I was visiting family on the east coast, but I’m back in West Texas and the 2008 - 2009 school year started at Presidio High School today.

We have a couple of iron-head Sportsters to work on and I’m looking forward to getting started.


I took the Knucklehead Special out Saturday and rode through the mountains to San Solomon Springs at Balmorea State Park, an enormous natural spring that was reworked into a huge swimming pool by the WPA during the 1930’s. I covered just under 200 miles of winding mountain roads at altitudes of 4 to 6 thousand feet. The weather was unusually cool for the Big Bend in August with temperatures in the 60’s and 70’s F. The day was cloudy and I ran in light misting rain for about half of the way out and back. The iron-lunged Knuck loved it and ran cool, smooth, and powerful at 55 to 75 miles per hour. I’ve got 2,600 miles on the mill and the more it runs the smoother it gets.


I averaged 33 to 35 mpg with the CV Keihin on the 80” engine. I might be able to do better if I lean it out some, but it’s starting easily and making good power so I’m going to leave it as is for the time being. The engine starts in 1 or 2 kicks when cold or hot; I sometimes have to kick it through 5 or 6 time when it’s half warm, as when it’s been sitting a spell, but maybe I just haven’t figured out how much throttle it likes. I think some of the carb problems I had may have been due to the aftermarket tuner kit we installed. All of the parts in the carb at present are OEM and it is working great.


I’m planning on taking a few days off from school in October and riding the Knucklehead Special to the Smoke Out West III Chopperfest and Chopper Show put on by The Horse – Backstreet Chopper Magazine in Cottonwood, Arizona, on October 3rd and 4th. http://www.SmokeOutRally.com Any of y’all planning to attend?


Anyhow, it’s good to be back and I’ve enjoyed reading about y’all’s summer adventures.


Later --- Randall

my main comment on 6v vs 12v systems is that a 12v system works more reliably, because it doesn't have to be 100% to work at all!

I certainly don't agree that 6v lights are as good as 12v or anywhere near, assuming you don't have a 5" Bates headlight and tombstone rear, in which case your lights aren't worth a bent ha'penny ( 'plugged nickel' for our transatlantic cousins ) at ANY voltage....

Randall, I've found hot starts are improoved if the idle speed is set a tad higher, either by pulling the choke out about a quarter inch( check the speed effect when the engine is running) or by twisting the throttle open just a bit, or just by setting the idle speed up, which may help oil pressure at idle as well. Just something I've experamented with, My B cam doesn't like slow idle anyway. Mike

Howdy Folks,

I’ve got just under 3,000 miles on the Presidio High School Knucklehead Special at this point and consider the engine to be fully broken in. The 80” mill is running smooth and strong. Now that the weather here in the Chihuahuan Desert has cooled with the coming of winter I find that the engine can be hard to start when the temperature is below 40F. It may be that I just haven’t found the right starting drill for the cooler temps. When the weather is warmer I set the enrichener knob on the CV Keihin, pump the throttle a couple of times, kick through twice with the switch off, switch on, open the throttle, and she starts in one or two kicks. Engine warm or hot and one or two kicks with a twist of the throttle will do it. Cold and I may have to kick it through fifteen or twenty times before she catches and runs. Part of it may be cold oil keeping the mill from spinning freely; I’m running Mobile 1 V-Twin 20w/50w synthetic but the motor feels stiff when I kick it through the first five or six kicks.

The bike cruises effortlessly at 65 to 75 mph and accelerates to 95 for passing with no problem. I am constantly telling my students to use Loc-Tite on all threaded fasteners, I can identify the few they missed by what falls off!

The only oil leaks I’m experiencing are a little seepage around the rocker tins, pretty much par for the course with Knuckles, based on my experience. I occasionally accumulate enough to get a drip on one or the other of the head pipes. I pulled up next to one of my fellow high school teachers in town the other day; he rides one of those swoopy Jetsons-style big scooters that are so popular for their fuel economy. A tendril of oil smoke wafted up from under my fatbobs. “Oh my God, Mr. Cater!” he cried, “Your bike is smoking!” I assured him that, given 60-year old design and technology, it was perfectly normal and nothing to worry about. He looked at me incredulously and whirred away, shaking his head.

The Primo primary belt and the Diamond O-ring rear chain have required no attention. I’ve had no problems with the CV Keihin since installing OEM parts. I’ve had no broken bulbs on the three rear tail lamps since installing LED bulb replacements. The 7” H-4 quartz halogen lamp in the King Bee headlight nacelle is an absolute torch and the Cycle Electric generator with built-in low output regulator has no trouble keeping it shining. The little dual-piston Performance Machine front brake we installed on the springer is doing a good job of stopping the bike. The stock drum rear will keep the bike from rolling at a stop sign but not much more. We arced the new brake shoes to fit the drum after we got them re-lined in Mexico, and I keep thinking they will finally bed-in and start actually offering some stopping power, but at this point I’m beginning to peruse the catalogs for a disc brake rear hub and sketch caliper carriers for a 4-piston Brembo I’ve got laying around.

I’m riding the bike mostly on weekends as it is dark when we go in to school and, frequently, dark when we return, but the weather during the days has been glorious, cool, with the sun shining in clear blue skies. I’m looking forward to Christmas vacation in a couple of weeks and some days spent riding around the Big Bend. I hope the weather is fine in your neck of the woods and wish you all a very merry Christmas!

--- Randall

Great news that it all seems to be working out. Riding on Christmas vacation - I'm jealous!!!! Up here (Ontario, Canada) it is quite cold now and they have salted the roads putting an end to the riding season.

Merry Christmas to all as well.

Brent

just came into the picture here randall
gr8 story about the ol knuck you got going
mite ii say
cold weather and hard starting makes me think you might want to check the valve adjustment but before you do recheck your cyl base nuts torque and also the headbolt torque
then readjust your valves you mite find the hard start go away you mite not but its a good place to start anyway
mike

Howdy Mike,

A valve adjustment is about due so I'll try that this weekend and let y'all know if it makes any difference.

Thanks for your interest! --- Randall

Randall, I've always had good luck with the stock drum brake, (well except for that time the shoes wore so thin that when I stepped on the pedal, the lever cam must have turned a full 90 degrees, creating a jackhammer effect which sheared off the brake cam operating shaft right at the lever.) Other than that hair raising episode, I've been satisfied with the rear drum brake. The front, on the other hand is completely useless... Mike

Howdy Folks,

It has been a year since I posted on the PHS Knucklehead Special so I thought I’d give y’all an update. I’ve put a little over 7,000 miles on the odometer; mostly weekend rides around the Big Bend. Everything has been working reliably with only a few minor problems. One of the LED tail light bulbs vibrated itself to pieces and had to be replaced. The tab welded to the fender rail supporting the chain guard proved to have insufficient penetration and disappeared somewhere on the road along with the chain guard. The o-ring chain doesn’t throw a lot of oil so I haven’t bothered to replace it. A few nuts and bolts have vibrated loose and had to be loc-tited. The rocker tins still seep a bit of oil.

In September I rode the Knuckle to the White Buffalo Rally in Snyder, one of the largest rallies held in West Texas. The ride was 400 miles from the Big Bend to Snyder, 200 miles for the poker run, and then 400 miles home again for a 1,000 mile weekend. I met up with a buddy who lives near there for the poker run and rode alone to and from Snyder. I run between 65 and 75 miles an hour on the open road.

The bike ran great on the way over, and I did a quick check of the sparkplugs and valve adjustment on Saturday morning before leaving on the poker run. The valves were fine, but I noticed that the sparkplug on the rear head was gray and there were signs that the crush gasket was leaking where it seated against the head. The heads, late-style big port OEM, had been stored for some years in a shed in North Texas where the damp conditions had rendered them rusty and somewhat pitted. We bead-blasted and painted them during the engine build, but there was enough pitting at the edge of the sparkplug hole that the crush gasket had failed. I installed a new plug and gasket, kicked her over, and left with my buddy on the run. As the day progressed the bike began to pop back through the carburetor and generally display signs of running lean. The symptoms decreased and the bike ran acceptably if I pulled the enrichener knob out a little on the CV Keihin.

Sunday morning I removed the plug and fashioned a crush ring out of heavy-duty aluminum foil, then reinstalled the plug. This held for about 60 miles. I made another and left the enrichener on and so made it on home. The engine ran fine but I could tell the rear head was throwing off more heat than usual.

I’ve got the bike in my shop now and guess I will pull the top end and look things over. I’ll set the rear head up in the vertical mill and spot-mill the sparkplug seat to clean it up, which should fix the compression leak. I’ll shoot a new clear-coat on the fatbobs and buff them out while they’re off the bike. It won’t be too painful having the Knuckle down for a month or two because I traded my ’02 Victory on a new ’09 Streetglide back in August, but that’s another story…

Merry Christmas to all! --- Randall

Interesting that the enrichener helped as although that circuit was open it's rendered mostly ineffective when the throttle is not closed.

interested to see the comments about LED lamps. I've seen LED units largely replace bulbs in recent years for mining caplamps, which are also a limited wattage/low voltage application, and the improvement is enormous.

Howdy Folks,

Its been a spell since I posted, about a year and a half, and also that long since I rode the Knucklehead Special. The fatbobs developed some cracks where the mounts were welded on after the high speed run to the White Buffalo and back and I pulled them off of the bike for repairs. I needed to repair the leak at the rear sparkplug and had some new intake clamps I wanted to try. Things got busy at school, the bobs got pushed to the back of the bench, I had the ’09 Street Glide to ride to work everyday… well, you know how it goes. A year had gone by before I knew it. I finally shamed myself into the welding up the cracks, remounted the tanks, went to kick her over and… I couldn’t do it.

I crushed my left leg and hip in a crash back in ’82 when an old lady turned left in front of me as I was test riding a customer’s Norton Commando. Several surgeries and 10 years on I had an artificial hip installed in 1992. That worked fairly well until a few years ago when it started to be increasingly painful to walk on. When I went to kick the Knuckle last October it hurt so bad I couldn’t do it. I had the hip replaced in November, was recovering, then got a bone infection in January. I spent 8 weeks in the hospital trying to get the leg cleaned out and am finally back home and returned to school, albeit on crutches for the time being. The doc says I should be back on two feet by mid-summer and I’m looking forward to getting back on my bikes.

What I’m getting around to is, kick-starting has become problematical. I’m looking at my options for fitting an electric starter to the Knucklehead Special. I want a reliable set up that will maintain the classic look of the bike as much as possible and cost is a consideration. I’ve talked to the folks at Techcycle and emailed Russ Peterson to inquire about his right-side starter conversion. Do any of you have any experience with these systems or others that you’d be willing to share?

Thanks --- Randall

[Pa]

Dang Randall... I was wondering why you had not been around for a spell. I hope you heal up fast and good. Wish I could help with the starter tech question but saddly I cannot. Pa

I investigated all those starters for my Knuck Bobber project. Tech Cycle requires surgery on the fender and the right side mount is just plain UGLY. I finally decided to use all genuine H-D stuff and keep the kicker for emergencies. I used a stock electric start tranny case with the '65-69 main shaft in it. Cut up an electric start inner primary to make the starter mount. A friend took a well used and abused motor sprocket and turned all the teeth off of it. He bored a large hole in a new sprocket so the old one will fit in it and welded them together allowing enough offset so the motor sprocket lines up with the sprocket on the clutch drum.
I used a later model import starter as it was over an inch shorter and wouldn't stick out past the bottom of the oil tank. Drill out and re tap the mount for the starter is all that needed to be done for that.
Now I am in the middle of the oil tank mods. I cut the top, bottom and rear center section out. I'm trying to find the smallest battery with the most amps so I can refigure the tank to accept it. Also need to put in a new bottom that will give clearance to the electric start clutch release lever.

Thanks for taking time to reply, Chris, and for your kind words, Pa. I saw some photos of Chris's set-up on another site and its pretty clean. I don't have the H-D electric-start parts readily available so I'm probably going to go with one of the conversions. I'm leaning towards Russ's RSES because its less expensive and easily put back to stock if I choose. I'm still trying to get used to the way it looks though, and I hate to lose the kicker, although I shouldn't be using it for my leg's sake. I guess there aren't many folks using these set-ups; I haven't gotten much feedback either here or at Iron Motors.

--- Randall