New BoardTrack Project w/Honda Engine

[vrgt2003]

Board Track Racer,

Thanks for the pic's, this is probably the direction we will head. The larger sprocket will probably give us some grief, may have to spread the rear stays a bit to get clear.

I assume you disassembled the rear hub. Is there clearance to use a nut on the inside?

Mike

 

[dmar836]

Vrgt, Well, that's an honor. Good to see others, like BTR, trying to do this right.
Mine is similar with the jackshaft running a secondary reduction. I ran the clutch off the crank though. In theory, I think yours is fine. The power from these engines is similar to those of the past - kinda herky-jerky. Hopefully this won't strain your jackshaft bearings too much.
On mine, a Worksman drum hub - like BTRs(got the part # from him) - there are three cast support webs so there are three areas where you could bolt. I'm not sure how Edward got six bolt heads in there. It looks like there are two bolts close together in each pocket in the hub. This appears to be the best option for this hub setup, and likely what I will do, but offers no cush drive. I will mill flats on the inside of the pockets and bolt there. Not the best idea as failure will likely be catastrophic. The closer you mount the sprocket to the hub the better. Mine is spaced about .600 out.
Here's a shot of the inside of the drum.

 

[vrgt2003]

Dave,

I will re-spring the clutch to engage at 1200 RPM. I have 2:1 reduction from the primary, so in theory I am about 2400 RPM on the engine when the clutch engages which is right at peak torque for this engine.

I was lucky to find a set of roller bearings that fit the bottom bracket races nicely.

Thanks for the pics on the HUB, would you happen to know the part number for the Worksman HUB.

Mike

 

[dmar836]

Board Track Racer does. I can't remember off the top of my head. These are the best wheels available IMO - except for the aluminum threads and weak brake. Great for a bicycle but not for a 150# motorcycle.

 

[Board Track Racer]

--------------------------------------------------------------------------------

Worksman industrial rims,

http://worksmancycles.com/shopsite_s...trialBikes.pdf

Rear: part# 77RA

Front: part# 77A

These rims are real nice, as David mentioned. The brakes are a little soft once you add all this weight, plus a rider. If you go this route, add some distance to your projected stop.
A definate concern is with the thickness of the hub face, there is not much. I drilled and tapped fine threads for the mounting of the sprocket, along with adding locking nuts to the inside. It's a tight fit (two bolts/nuts per section), but I squeezed them in. I mounted them as close to the center of the inside of the hub as possible, so I can still get a socket on them.
The above part numbers are for: 26" drum brake wheels w/o tire.
Dave, checked your Blog!...Thats a mighty big smile your wearing at Ralph Wayne's Backyard Nationals.


footnote: What are your plans for the first large sprocket off the motor? If you have access to a lathe I would trim it down a bit to get rid of some weight, and ease up on the Jackshaft bearings. (jmo)

 

[vrgt2003]

BTR,

Thanks for the part numbers on the Worksman's Hub and the suggestion on the sprocket. May try to to lighten the sprocket up by adding some lightening holes.

Mike

 

[dmar836]

BTR,
I think someone had just said or yelled something at me. Maybe I had that look on my face the whole time - it was a blast to finally ride it. More fun was gagging it when the crowd would clear enough. It was back firing(lean-never rejetted it) and spitting loudly - sounded great! I'll post some video a friend took once I get it.
Dave

 

[wildwestrider]

beautiful BTR you are putting together VRGT. Whats the story on the Healey in your early thread pics?

Brian In Austin

 

[vrgt2003]

The picture earlier in the thread of the BTR is what I'm guessing is a mid to later 1920's Indian BTR. Both Indian and Harley had small displacement single 21 ci street bikes by the mid 1920's. Indian was first and named theirs Prince and I believe the Harley was the Model B. Both of the models were modified into boardtrack and speedway style racers. The most famous was the Harley "Peashooter". These bikes dominated the single cylinder OHV racing class.


Since we are building a somewhat larger looking single cyclinder BTR, I am trying to follow the mid 1920's style of racer. I not sure if Indian had a nickname for their racer like Harley had the "Peashooter" for their single cyclinder OHV racer, but I think we are far enough along to name our bike.

After some diliberation and a few beers we have settled on "Cherry Popper" as the name for our bike.

Mike

 

[Clotho]

Hi!

Great project. Looks like it is coming along nicely. I have one question.

In all of your pictures you show the engine without the shroud. Do you plan to run it like this or is it just in the way as you are working on it?

Keep up the good work!

 

[wildwestrider]

Mike, the Harley is a beautiful bike, but,....was actually asking about the "Healey" as in "Austin Healey" 100 or 3000 in the back ground of one of your first Mock up pics (I've had 2 100-4s and did a full on show resto on a 61 BT7 Healey 3000). There is just part of the hood and a headlight bucket showing. Apologies on the thread Hi-jack. Had to ask. Brian

 

[dmar836]

Please:
a) Leave the shrouds off
b) Don't put "Cherry Popper" anywhere on the bike

JMO

 

[vrgt2003]

Mike, the Harley is a beautiful bike, but,....was actually asking about the "Healey" as in "Austin Healey" 100 or 3000 in the back ground of one of your first Mock up pics (I've had 2 100-4s and did a full on show resto on a 61 BT7 Healey 3000). There is just part of the hood and a headlight bucket showing. Apologies on the thread Hi-jack. Had to ask. Brian

Whoops, read right over your "Healey" question and read it as Harley. Yes that is a '61 BT7 in the pictures. One of my projects I intend to finish one day. It's in pretty tough shape. We have stripped it down to the frame, had the frame sand blasted and primed. Put the body work back on just to have a place for it. Love to see pictures of your Healey's.

Mike

 

[wildwestrider]

You can see my BT7 at the North Texas Austin Healey website under pictures of cars of former members or, try this link. If it works,..it will take you directly there. Brian

Untitled Document

 

[vrgt2003]

Dave,

We plan to keep the shrouds off the engine. I saw where you had the fins cut off and turned down which looked great and we hope to be able to do the same with the Honda engine. Obviously we are concerned with the cooling but are willing to take the risk. Has there been any issue with overheating with your V-Twin?

"Cherry Popper" is a play off of Harley's "Peashooter". When I was a kid my Dad showed me how to make what he called a cherry popper. We had bamboo and a couple of cherry trees in the back, it was great fun. Although we are taking cues from the Indian 'Prince' racer, we really are not close enough to name the bike after Indian or Harley. I know there is a down side to the name but I think it will beg more questions about the history of these single cyclinder racers. Give it a chance.

Mike

 

[vrgt2003]

You can see my BT7 at the North Texas Austin Healey website under pictures of cars of former members or, try this link. If it works,..it will take you directly there. Brian

Untitled Document

The link worked fine. What a great looking Healey. Are you able to fold the windshield down like the 100-4's. It sort of looks like a 100-4 winshield in the picture. Love the color scheme. Fantastic job.

Here is a picture of the Healey when my father had her.


Mike

 

[wildwestrider]

Actually in the first pic showing what looks like the windshield is installed....its actually just the posts....was waiting for the trim to be re-chromed. I cracked the glass when reistalling it..............so, decided to just leave it off..................(;>

The link worked fine. What a great looking Healey. Are you able to fold the windshield down like the 100-4's. It sort of looks like a 100-4 winshield in the picture. Love the color scheme. Fantastic job.

Here is a picture of the Healey when my father had her.
View attachment 14474

Mike

 

[dmar836]

Mike,
I can appreciate the historical tie.
I have not had overheating issues but don't run it that much. It was built just as a fairgrounds cruiser and I have had no issues.
Keep in mind that with shrouds these engines were designed to be in mostly enclosed or in walking-speed machines. Open air circulation helps a lot but certainly wouldn't be enough without moving around a bit. The fins themselves without the shroud are really not functional. I have seen some newer engines with plastic fins mounted to the flywheel(perfect for us!). One might argue the need for heat sink material but certainly not on the flywheel. What I would argue is that, especially with a single cyl, the heavier the flywheel the smoother the power transmission to the ground. With a single power stroke every other revolution, you'll want to keep some weight on there to smooth out the pulses of power.
Dave

 

[markeatmark]

I see where you are going with the fake push rods. and i like it. can you find a way to leave off the valve cover? expose the rocker arms?

 

[vrgt2003]

I think we might try to give a side valve look, sort of like the Harley B26 single.


Add the fake pushrods and fabricate a fake flathead and attach it right to the top.
Should be able to have verticle fins on the top.

We hope to leave the flywheel exposed. We will attempt to cut off the fins and skim the top leaving a smooth finish. This may expose some casting voids so we are not sure what to expect.

Mike