[oupa]

I’ve made several individual posts concerning the various parts I’ve made as this project progresses. As those posts accumulate, I’ve decided to put them under one heading. I neglected a project log until now because this has been a sort of piecemeal undertaking. I originally brought the major parts home more than five years ago never intending it as more than spare parts for the more-or-less complete bike that it came with. The frame & engine discussed are seen here on the ride home flanking the sister bike.


The sister bike has a title. This frame does not. The sister bike had a complete, but at the time non-running engine & trans. This one was incomplete. I didn’t know at the time and I still don’t know yet if this one is even going to run and drive. While it is intended as “a race bike,” I have not done any performance work to the engine. First, I want to know if it’ll even work! As for racing, I’m 60 years old. I haven’t been on a track since I was 15. “Performance” is subjective at this stage.

I began with a 1971 K1 SL 350 engine and frame, that’s about it. Along the way I picked up a front end I’m not totally sure of the heritage of, a pair of mismatched 19” wheels, a Kawasaki 250 Ninja rear brake and probably a few other odds and ends I’m forgetting. I’m using a 75ish era XL350 tank and a modified fiberglass tracker seat/tail I had on hand. Many other parts have been shop built mostly because I wanted to. This is first and foremost a project to kill time and especially learn. Hopefully, without breaking the bank.
If you’re looking for guidance on how to restore your bike, how to recreate obsolete parts, save money, go fast, or a million other legitimate goals in working on a vintage Honda, this probably isn’t the place to look. If you’re in search of expert advice, you’re definitely on the wrong page. If however you are looking for entertainment, I just may be able to fill the bill.

Before getting too far into the project I stripped the frame down and checked to make sure it wasn’t tweaked. Looked good. Unnecessary bits were removed, with some left on because they would be repurposed for attachment of new parts and some… just because I hate cutting up old bikes.
The tank like several other parts was originally intended for another project. Since the XL is a one-lunger, some means had to be contrived to feed both SL carburetors. The XL also has a slightly smaller bung/threads on the tank so you can’t simply screw on an SL petcock. You can buy plastic “Y” fittings cheap enough from the usual vendors but what’s the fun in that? I turned the applicable parts in brass and soldered them together. My single spout XL petcock now feeds twin SL carbs! I was originally concerned about volume delivery, but previous testing on another SL proved this to work. You really only need enough fuel flow to maintain the bowls at (about) ½ full, so the worry about volume is really overblown in my opinion.


The SL tank also uses slightly smaller front “bumpers” than the SL/CB/CL tank. An adaptor was easily fabed out of 12ga. Steel, formed to the frame backbone, two “nubs” welded on and the whole tack welded to the frame after establishing where I wanted the tank to sit. The tunnel is smaller. It does not allow the tank to seat completely on the frame, but I wanted it higher anyway. An attachment point for the rear of the tank and front of the seat will be worked out later in the process. Falling off your motorcycle is never a good thing. It is typically less expected to happen in casual and recreational riding than on the track though, so for this project making absolutely sure the gas tank is SECURELY attached to the bike is maybe more critical than usual. I don’t plan to fall off. Falling off is still an exception rather than a rule, but the prospects of it happening increase. Not being ready if it does is unacceptable. Helmet, gloves, boots and leathers? Check! All parts attached securely? Check! Insurance — health & life, paid up? Check!

 

[oupa]

One of the other one-off additions to this project was my cam chain roller. Below is the link to the original post/discussion while I was making it.

https://www.hondatwins.net/forums/48-engine-discussion/123350-custom-cam-chain-adjuster.html

 

[thadf]

Loving the write up so far. You have a light hearted sense of humor that I like. Very good.

I’m doing a cb360t at the moment. A sense of humor is an absolute necessity for maintaining sanity, at least for me anyway

Looking forward to seeing more. Oh, and WOW with the turned parts!!!


Sent from my iPhone using Tapatalk

 

[oupa]

Another recent experiment began when I ran across an orphan shifter linkage in a box of odd parts one day. If you're unfamiliar, dedicated flat track bikes often have both shifter and (rear) brake on the right side. I turned that linkage over in my hands and wondered, what if... I have since finished up the design and fabrication (I think).

It took most of a Sunday but I came up with a working device made out of junk lying around the shop. At least it works on the bench. Still debating on adding a zerk fitting or two to the housing tube. There is really nothing to be lubricated except the bushings on either end, but keeping it full of grease may help exclude water from collecting and causing rust.

Here's the link to the original post and discussion while working on that task.
https://www.hondatwins.net/forums/53-miscellaneous-discussion/124836-shifter-relocation.html

 

[oupa]

Next was my UGLY exhaust.
https://www.hondatwins.net/forums/53-miscellaneous-discussion/125082-building-exhaust.html

As mentioned in the individual post, I used (mostly) 1 1/4 inch EMT electrical conduit. I have no idea how it may hold up - or not. Since it will see minimal use annually, that may not be as much of a concern as a regularly used street or trail bike. Then again, sitting around sometimes has a way of being as bad or worse than using things. As I obtained the pipe free of charge, it was a good medium to learn some basics of an art form I'd never done. This is a ferrous metal. Calling it "steel" however is patently unfair to steel. Man, does this stuff weld nasty!!! Granted, I'm a long way from being even an okay welder, but the difference when I finally got to where I joined a piece of purpose made EXHAUST PIPE to the device, the difference was immediately visible.

I have A LOT of slag to clean off. A LOT of globbed up weld. Having done quite a bit of that already from the first attempts though, I've discovered that under all that nastiness, the pipe typically joined very well. Another concern for grinding those welds down though is they are going to rust at each joint. My intent is to wrap the head pipes. That means the appearances won't be a huge factor in the finished product. The soundness of the joints and their longevity will however!

I'm more than a little concerned about the layout and design. Each joint is (typically) two 30 degree cut ends welded together to form a 60 degree bend. To most of we uninitiated (or mildly interested :-? ) exhaust design is a kind of black art unto itself. There are certain principles that are known to do certain things. There are rumors and beliefs that other things will do other things and the whole is pretty much voodoo to those who always thought the exhaust system was nothing but a conduit to carry excess noise and fumes away. Every function of your engine is important. It is as equally distressed as you would be from either diarrhea or constipation.

I hope to have some time in the morning to clean those welds up and cut one or two of the brace straps back off. The pipes are merely lying against the engine in this photo, NOT attached as in some previous ones during construction.


BTW - As I do not have access to either a bandsaw of chop saw at present, all this was cut with a hand-held reciprocating saw. It was really tough holding the pipe and I got several great suggestions in the individual thread on this part. I ended up however using a compression-style (conduit) coupling to hold small pieces. Worked great! Held it securely with no threat of crushing the pipe and the fitting can be clamped very securely in the vise again, without threat of crushing the pipe.

 

[oupa]

Finished up the 2-into-1 collector unit yesterday then wrapped the entire exhaust back to it. Still undecided what to do about a muffler/silencer.
This was my first personal experience with exhaust wrap. If not for the sharp bends, closeness of the two pipes and the connector (primarily an anchor point for eventual heat shield) the actual wrapping would be simple. :grin:

 

[Pops]

Following this thread with GREAT interest - especially since I'm also attempting to resurrect a basket case SL.

 

[oupa]

Spent much of the day in the shop. No photos as I was BUSY! Finished up the new foot control & rest plates. Well, not "finished," but design and fitment is finished at least. I'll work on making them a tad prettier later on. Made the new pegs and installed them. Racked my brain trying to do the calculations for sprocket offset with the wheel I'm using, but since I STILL don't have the right bearings I won't be able to finish that task until I can actually install the wheel and line everything up. I did bore and turn the anticipated spacers though. Not sure if it'll be tomorrow or not, but next on the agenda is the new break pedal. That should have the foot controls buttoned up. When I get back to it I'll grab some photos to update the log. My back is KILLING me!

 

[ancientdad]

My back is KILLING me!

I know that feeling... a long day in the garage translates into a lot of lower back pain from all the continuous standing. Even with a lift, not much can be done while sitting on a stool of any height, and it wears you down

 

[oupa]

Here's the finished left-side rest.



The right side took a bit more planning and work due to incorporating the new brake - pedal and master cylinder.



Here's a not so great photo of the brake pedal roughed out and fitted up.



And the finished right-side rest with brake.



The dangling reservoir will be tied up on an extension from the top rear bolt in the aluminum plate. I'm really trying to avoid much more work around the rear wheel until I can get the wheel mounted up. Might start in on the tank and seat while I wait and the weather is nice.

 

[oupa]

Following this thread with GREAT interest - especially since I'm also attempting to resurrect a basket case SL.

Pops, There's a race at the Shenandoah fairgrounds at Woodstock on Aug. 24 ya know.

 

[Pops]

Pops, There's a race at the Shenandoah fairgrounds at Woodstock on Aug. 24 ya know.

Oooh, I didn't know that. May have to add it to the calendar!

 

[oupa]

Oooh, I didn't know that. May have to add it to the calendar!

I tell everyone with even the most remote interest in flat track racing that they should see the Barbara Fritchie Classic in Frederick, MD. at least once. 2019 will be the 97th annual race on this same track. The oldest continuous 1/2 mile in the country! Barbara Fritchie Classic ? JULY 4TH 2017 Motorcycle Race Frederick Md

You're not that far away. Practice starts about 10 AM. Qualifying about 12 and the whole thing usually wraps up by 5. July 4th is the one day of the year my wife knows where I will be.

 

[oupa]

Size concessions necessary to get the right OD wheel bearings meant making a new axle and modifying the spacers yesterday. Not a big deal just time consuming. Touched up the white on the old tank. The red still needs a touch up as well then a good overall clean and seal coat. Since she's finally on her own two wheels I brought her out into the light of day for a photo. Doesn't look like much but there's a lot of work in getting this far from the bare frame I began with. Still a lot more to do!

 

[oupa]

I've neglected updating this log lately. The reason however is because I have been pretty busy actually working on the project. To that end, I'm afraid there aren't any nice photos to accompany this update to give you a clearer idea of what I'm describing. Very simply, I never stopped to take any. :-?

I've been bouncing between various tasks as need arises. I finally got the needed bearings. I'm using an 81 Yamaha SX 650 alloy front wheel for a rear wheel. Yeah, you read that right.
Anyway, I finally got the bearings in one day this week (what day I don't even know anymore ). That allowed me to finish making the applicable spacers and... as it turned out, another new axle.
Been working on and off the last several days on the adaptor to connect a sprocket to the wheel. I cut a carrier plate from 1/4" aluminum, which in turn is bolted to the wheel via the original (dual) brake rotor holes. There was A LOT of calculation and measurement involved in that little project! Bolting up a four-hole sprocket to a six-hole wheel and getting it all the right distance from the hub so the rear sprocket is aligned with the front sprocket, which I don't have yet... This job won't be able to be finalized until the new sprockets arrive sometime this week - I hope. I expect to be pretty doggone close though! By the way, I'm using the original brake rotor on the other side.

Let's see, what else? Touched up the paint on the old seat & tank. Fabed a bracket to support the tail of the tank and the nose of the seat (it's 1 1/2" higher than the frame). Tore the motor back down to the pistons and reassembled, double checking everything as I went. Previous assembly had been done temporarily with intent of this process as I near the point of install - which I am. I trimmed up the front sprocket cover. Partly for appearances. Partly to make sprocket changes easier. The rear of the cover was given a wide arc from the top to near the bottom rear bolt. This was made to (just!) miss the support ribs cast into the inside of the cover. I also cut a 2 inch hole directly over the counter shaft. This should allow removing the sprocket without having to remove the cover, along with the shifter and clutch actuator. I had to remove the stator cover to clean the mud dauber larvae out of two bolt holes that didn't have bolts. :-? Two of the bolts that were present were so buggered I had to slot them and gingerly use a straight blade in the old impact driver. While I had it apart I cleaned up the grimy stator and cleaned the rust and aluminum oxide off the bolts holding the coils to the cover. Reassembly was with all new socket head SS bolts. The closest ones I had on hand were 6X40mm, so most had to be shortened to 35mm. I know there was more but it's all kinda running together at this point. Hate to lose momentum but I really need to step away for a day and let my thoughts re-gel.

Still on the fence about the electrical system. I really prefer to eliminate the battery. Not so much for weight savings as merely to simplify the system so I don't have to worry about a charge on the battery. Just haven't decided yet. :-?

 

[oupa]

My apologies, but still no new photos. I received my new sprockets today. Selected from what was readily available, I have a 16 X 42 front to rear. That should give pretty decent torque for short track use, but gearing choice is one of those things way down my list at this stage. It can always be tweaked later... providing this thing actually works! I had enough time after supper tonight to install the front sprocket but the rear is going to be a bit more time consuming since it involves tweaking wheel spacers for sprocket alignment. The good news is, at least now that I have them, I can finally do that alignment thing.

If you missed it I have another thread discussing the pros & cons of going batteryless here. It's something I've decided to try. I'm picking up a R/R at the local small engine parts supply tomorrow. I have a bag of capacitors and a set of old, but good coils from another SL 350. These are being mounted on a bracket under the seat just behind the backbone down tube. This "bracket" is nothing but a piece of 1/8 X 1 1/2 inch steel strap between the brace where the tail of the tank originally rested to the bridge under the original seat. There are two convenient 6mm threaded holes (one each) in these frame parts that I bolted the bracket to. [the photo in post #14 has a washer lying on each of these holes] The electrical parts will be together there as well as having some protection from both weather and roost.

One reason I didn't have much time today is because I spent much of it picking up Luigi, my 250 Aermacchi from a buddy who is somewhat of a specialist in them. He rebuilt the engine with new rings seals and... a new crank :-? for me last winter. If you think finding parts for old Hondas is tough.

 

[oupa]

The new footrest and brake master cylinder bracket required the kickstart lever to be modified somewhat. It remains to be seen how well this is going to work, but it's the easiest of several options at this stage.



The sprocket cover I picked up had some obvious chain wear on the inside. Since it isn't for this particular model anyway, I decided to trim it up a bit to avoid more of that. I also cut a hole over the counter shaft to allow for changing sprockets without having to remove the cover. Trust me on this... the hole is ROUND! It's an optical illusion from the step in the cover that's been driving me mad since cutting it, but it really is round. :-?



Here's the bracket I made to hold all my non-engine mounted electrical devices. The R/R will be installed just behind the coils. I haven't quite decided on where to place the capacitor yet but it's so small that shouldn't be much of a challenge.



Here's one of the capacitors I picked up. This thing is puny! It is however the correct rating recommended by several. I'm still in disbelief something this tiny can do what it's claimed, but I'm gonna find out! User Simo uses two 10,000uF units successfully so at worst I figure I may need to wire five together. The plus side is they're six for $10!

 

[ancientdad]

Here's one of the capacitors I picked up. This thing is puny! It is however the correct rating recommended by several. I'm still in disbelief something this tiny can do what it's claimed, but I'm gonna find out! User Simo uses two 10,000uF units successfully so at worst I figure I may need to wire five together. The plus side is they're six for $10!

View attachment 281212

I suspect the punyness is because they are 4700uF, as opposed to 47000uF you mentioned in the Battery elimination thread

 

[oupa]

I suspect the punyness is because they are 4700uF, as opposed to 47000uF you mentioned in the Battery elimination thread

Possibly!

I need to go back and look at what I ordered. As well as what was recommended. Several videos (and you KNOW youtube is a reliable source ) used caps about this physical size. Unfortunately, the dialog was either in a language I don't understand or with such a thick accent, I still couldn't understand. I don't know whether I ordered the wrong ones or they sent me the wrong ones. I suspect the former though. The plus side is that I can still wire them together for a cumulative (recommended) value. To that end, six for $10 as opposed to one 20,000uF unit for $40 isn't anywhere near a deal breaker... IF it works!

For anyone considering this mod, I would recommend the commercially offered units sold for this by various vendors. After shopping around, the 20,000uF + capacitors aren't much less than the marketed "battery eliminators." Established vendors selling them are much more likely to be supplying RELIABLE parts. Ordering from Amazon or ebay is a crap shoot, probably with the odds somewhat against you where electronic components are concerned.

 

[oupa]

correction

THIS POST IS BEING REVISED TO REMOVE UNADVISABLE INFORMATION AND REPLACE IT WITH THE CORRECT PROCESS FOR ASSEMBLING THE CAPACITOR.
For anyone who has read this already in its previous form, the process is the same. The resulting increase is the same. The specific wiring of the capcitors in the previous post was incorrect however and is being corrected.
Apologies.
oupa

This should give me 28,000+uF of power. ...I hope.

The leads were left about 10-12 inches long and are taped to the outside of the fitting here just to keep them out of the way during the pouring process. Once everything sets up I may put a couple wraps of tape around the top and fill it above the rim with more epoxy. It doesn't look like it in the photo, but all the wires are covered, but it never hurts to be sure.