The Hodaka Club Forum

You have certainly read up and researched the subject adequately. Give it your best shot and if it breaks, improve it. All these niggling details can drive one nutso, but it is so nice to look at the product years later.

Thanks Jack. I think we all agree that holes weaken parts. I admit that if I want to reduce weight, the quickest way is to put the rider on a diet. I could easily give up five pounds rather than weakening parts grams at a time. Art is part of this project so I'll have to design the part to meet requirements rather than to be as strong as possible as in overkill. A fine line sometimes. I find aircraft an interesting design and challenge for the designer. It must be strong, light and aerodynamic. Lotsa holes are drilled to meet the weight requirement. It all adds up. Or a spacecraft where grams are big money in launch costs and/or payload limits. I guess what I'm saying is that I have the problem, I'm trying to build this project with some parameters. In this case it is like an aircraft. Requirements are similar, light, aerodynamic, strong, fast, hopefully safe and should look good with innovations. I don't know if I can meet all these requirements. Projects like this are a challenge, a game to me, a giant model or piece of art. All quite entertaining I might add!

Just rambling and being philosophic this rainy day. I always appreciate your and others advice. Part of the game is to please the Gang!

Max

I've always liked the design aspects of your drilling and lightweight creating effects, Max. You did a similar design & function with the previous chain guard on the last project. It was fun to watch! Again with this piece, it DOES have a rather aerodynamic aircrafty (pun intended) look to it. And I'm assuming you'll use the same design but reversed for the other side? And then there will be the relocation of the brake pedal as well! Good luck & I can't wait to see the final results for both sides! ,Victor

Art is part of any project. Verily so.

One rule of thumb on RC aircraft built for competition, which have to be light and strong: make the part lighter and lighter til it breaks, then strengthen it so it doesn't break.

Hmm, I haven't had to construct a cone for several decades but I took on the challenge. This project is supposed to be educational. Home-made does't mean hiring it out. After I got the mounting bracket cut off, I did remember that a cone is part of a circle. Two rulers determined the angle and radius and my stick compass marked the circles. Now the fab guy can play with the cut-outs before cutting the piece out of metal. Fun.

Maxie

Actually, the math is fairly simple. If you have the diameter at both ends and the distance between the two circles, the angle becomes automatic! Victor

Hmm, more than one way to skin a cat. I had to start somewhere!

Max

True! And is there anything inside that cone or is it just an open expansion chamber? ; D Victor

Here is an easy way to design the cones. It is a cone calculator. Go to this website:

http://www.cmrp.com/cone-calculator

Just input the numbers you have and it will do all the work.

Thx.

I've been worrying how are we going to keep everything in position when the cone is replaced. I built this quick jig that should make fitting and alignment easier. The cone to be replaced is in contact with the base board and everything else is shimmed to fit. Should work. Only two screws for transport and the pipe snaps in nicely.

Max

And thanks DR, I did play with the calculator but I had to draw it anyway for the pattern.

And Victor, the only thing in the pipe is a slip-in silencer that goes in the stinger.

Well, I kinda figured with this kind of pipe. Hoping the metal shaping goes as well for you Max! Victor

It's been decades since I built an all out Hodaka engine. All speculation and questions at this point but I have began to shop for or at least discuss a carb for this project. Road racing and top speed are top considerations but performance street is not out of the question. All our race engines of the past used 32mm Amal concentrics but that was a long time ago. What's the modern consensus on brand and mm. 34mm too big? Amal/Mikuni? Opinions? Displacement will be 100cc. Personally and historically I'd like to stick with the proven Amal, but Mikunis are half the price new and Mikunis are certainly proven equipment.

Max

It depends on what the bike is going to be. Will it be a concours, parts-correct bike of the type of that era? Or will it be your interpretation of a bike of this type using current parts and technology. Your "daily rider", so to speak. The Amal is a fine carb but is it necessary to complete the vision if this bike? The Mikuni is a good carb and it's practical.

But Jack on a hot day it looks cool. Maxie uses the cosmic look. If it doesn't function he will reinforce it or put it in the recycle box----- Clarence

I'd say if the Amal was your go-to high performance carburetor in the day, it will be just as much so today. There are also a lot of other variables to consider such as any planned modifications to the induction system, engine porting, ignition, and performance enhancements to the carburetor itself such as flow-direction vanes. I would suspect that the most applicable high performance technology for vintage 2-stroke motors occurred before there was such things as "vintage 2-stroke motors". That evolutionary process ground to a halt with the introduction of more sophisticated ignition systems, fuel injection, water cooling, power valves, and the more wide-spread use of 4-stroke motors. That's my 0.02.

My early day racer ran better with the Amal it was tested by Harry and he formulated the jetting for it. It did wear out quickly, in my opinion --------------Clarence

I should throw in the fact that there are no rules on this project. It's to keep me out of trouble my wife jokingly says. I'm also not off to start a new research project to re-invent the wheel and Hodaka or set land speed records. It should loosely follow the rules of vintage as it is vintage. So am I for that matter. My master plan revolves around the theme that Hodakas were designed to be modified. It started the day I bought my first Ace 90. It should be somewhat show quality because taking bikes to shows is also fun. Multi-purpose I say. One could even ride it!

Goals make projects fun and provide direction and innovation. One problem is that I have several of these finished projects filling up the shop. A GPS timed top speed attempt with old technology could be fun. One Last Great Race? Nah, I'd better say I'd done that. A couple of times actually. One can only have so many Last Great Races. A show bike. Always a fun day at shows particularly at different places and agendas. I guess it makes me socially acceptable in motorcycle circles or at least I hope so. A social thing. All justifications and even something to improve my amateur writing career.

Sometimes you have to ask yourself why you are building this thing? Entertainment? Social graces? Self esteem? Fun? Fun is getting closer but I think it's all of the above plus problem solving never hurt anyone especially as I age. Brain exercise is good. Tool use is good.

Thoughts for the day---

Maxie

Don't forget being an educational resource for the rest of us. The finished product is cool, but the process, the decision points, and the problem solving maneuvers from concept to completion are WAAAAAY cool.

Kinda off subject but I'm never satisfied with coatings or finish of Hodaka side covers. Paint looks good for a while but takes some hits and begins to chip. Even more off subject is frame paint. Powder coat looks really good but damage repair is difficult. I'm kinda in the rattle can world of something repairable for the masses namely me. Back to side cases. I really like the prototype blasted look. I usually blast the side cases and spray with WD-40 and wipe them before a race or even a ride. They clean up nicely with cycle cleaners and look good with another wipe down of WD-40. I've been using a Krylon paint product labeled Metallics. A flat aluminum paint that sprays on smooth, dries quickly and is easily retouched or sprayed, somewhat durable. I use it on fabbed steel brackets and metallic refurbed fasteners and parts like brake plate braces and such. It dries to a really nice flat aluminum and has become a part of my restorations.

I've tried re-painting side covers, blasted covers, black side covers, polished side covers, all somewhat temporary. The next test is a blasted side cover with a coat of Krylon flat Aluminum coating. The test I sprayed on this head looks good, not that you would use it on a head or other hot parts, but really doesn't look too bad. The plus is that it retouches easily and if you can remove it with carb or brake cleaner if you don't like it. I've got some extra cases in the blast pile and will test this idea soon. Hopefully this will give us another option for proper or at least repairable side cover coatings or finishes.

Max

Max I don't know what your porting consists of but a 100 ported decently can surely handle a 34mm carb and with the of venture dividers and a UFO it will behave small and perform big here is an example picture . Last month a customer of mine set a world record at Bonneville for 50cc with a Honda NS 50 that I ported as well as did carbs for him , I built a 24mm and a 28mm , he ran with the 24mm , He made the first run at 94.5 mph and the second at 89.5 mph and the averaged it at 91.5mph which beat the old record of 85.7 . A notable mention was that the customer said with my carb getting rolling of the line was mush easier and clutch slipping was not needed as with the old set up he ran last year. Also he was clocked at 97mph past the traps. He is working with the 28mm carb this weekend on the dyno for next year. I'm waiting for pictures and testimonial from him to post on my web site.

Rich

Thanks Rich. Cool stuff. I was hoping for your input. The engine is quite a ways out in my slow project but gathering up ideas is part of of the deal.

Max

On painting engine parts:
The Beemer has a natural sand-cast finish, unpainted, that weathers to a nice patina. I knock the oil, dirt and mud off with degreaser every couple of years whether it needs it or not.

The painted side cases on the Hodaka seem to be wear items that will chip, scratch and dull, and will need to be repainted every 2-4 years.

The cylinder head is media-blasted and has a light wire-brush on the flat outer fin surfaces as an accent.

The cliche frame finish nowadays is powder coating. Tough, durable but not retouchupable. My preference is s rattle-can epoxy or urethane paint.

My 2c.

Interesting story on the new cones for the damaged pipe. Fifty years ago we would take a drawing to the local sheet metal shop and a guy named Gordon would whip you up a set of cones to make a pipe. My old short tracker that I still have hanging around has these specialty parts. Gordo, I called him, retired many years ago and still fiddles in his shop. Wow! Just like the old days, I'm off, taking a pattern to Gordo for cones!

Next it's off to my clever guy Rodney who builds Hot Rods and specialty exhaust. After I showed him the drawings of the cone I figured out he said to add 1/4" on all sides to allow for adjustment. Just for laughs I had Gordo make two cones, One to my specs and one to Rodney's specs. Hopefully mine will fall right in there making my point, well maybe.

In other news, today is the day of the annual Dawg Daze Car Show which this year decided to drop motorcycles citing "lack of interest". Eweleen and I decide to boycott the event for our "lack of interest'' after all our years of participation. New management we think. Things come and go. Not bitter but disappointed in their thinking.

Well, that's my report, things moving along slowly, actually at my pace.

Max

Ah, the new rear sets have arrived and all looks well. I still haven't pinned the riding position down to finalize the mounting plates. I was a bit bogged down trying to visualize all of this and having parts in hand really helps. The controls look as advertised, adjustable pivot arms, made by a guy in Arkansas and reasonably priced at $80 with free shipping. I've been shopping shafts, rods and ends for the linkage, all cheap and available. I'm also waiting on the back ordered rear tire which would make the ground clearance to foot peg distance easier to measure.

Maxie