Second build - Questions

[Rusty_S85]

Well I am planning out my next build which I had always wanted to do. When I got into this with my first build I planned on it being a 2 stroke retro cruiser with the intent of a second build to be a pure vintage board track racer with a 4 stroke.

Well needless to say I will be using parts from Sportsman Flyer to do my build.

How ever I had some questions for people that have gone this route before.

First off the pictures and videos and even the photos of the completed bikes that Sportsman Flyer sells shows the 4 stroke engine is stripped of all external coverings as well as the pull start. Some look to have the old style outboard motor pull start you wrap around and pull while others have something completely different.

So first question is what options are there out there for starting the 4 stroke engines ?

I'm leaning towards a prediator 212 cc engine for this build.

I might have other questions but as of now this is what I will start off with. My goal is to have a Indian board track racer build that looks like the following Bonneville flyer from Sportsman flyer.

 

[Frankenstein]

Pretty sure 212 has an electric start option, some of their pumps and generators are equipped if I remember right. I have a friend who has put 3 of these and working on a 4th into bikes, he uses a pull start, key lock for engine ignition. Pull start really isn't bad, and even if the cord rips you can make a quick fix, electric start fails and you can't start at all.

On that note, you can get a manual clutch for these engines, you can adapt down even to the 49 and 79, you get back bump starting, but you lose the option to use something like a torq-a-verter which changes between 2 gears automatically. Pedal starting a 212 would be a b**ch, but if you keep the pull start you resolve that problem, using electric start you have a backup plan, the same used on millions of manual transmission vehicles with dead batteries/starters. You push the b**ch down a hill.

Options ain't bad, depends on how much money do you want to spend, and do you want that nice manual clutch since a 212 can handle anything, even with just one gear.

 

[Rusty_S85]

Pretty sure 212 has an electric start option, some of their pumps and generators are equipped if I remember right. I have a friend who has put 3 of these and working on a 4th into bikes, he uses a pull start, key lock for engine ignition. Pull start really isn't bad, and even if the cord rips you can make a quick fix, electric start fails and you can't start at all.

On that note, you can get a manual clutch for these engines, you can adapt down even to the 49 and 79, you get back bump starting, but you lose the option to use something like a torq-a-verter which changes between 2 gears automatically. Pedal starting a 212 would be a b*tch, but if you keep the pull start you resolve that problem, using electric start you have a backup plan, the same used on millions of manual transmission vehicles with dead batteries/starters. You push the b*tch down a hill.

Options ain't bad, depends on how much money do you want to spend, and do you want that nice manual clutch since a 212 can handle anything, even with just one gear.

Interesting.

I don't think I want an electric start. Would require me to mount a battery. I don't mind a pull start if its like this one shown here in the video below I found.



My problem is I would want the flywheel and clutch to be enclosed more like the following.

Personally I just think it gives a more professional look to the build with the clutch and the flywheel hidden from view.

On the clutch I saw there is a mechanical clutch available but I am really starting to think I would like to go automatic clutch on this one. The automatic clutch that is sold by this company is actually a high dollar motorcycle/automotive grade that is very bullet proof.

Torq-A-Verter? How does that work? Never heard of it till now?

Engine was I have my eyes set on the 212 at the bare min. Leaning towards finding a hemi 212 predator engine for this build. I'm also leaning towards a billet DynoCams aftermarket cam for the engine, specifically the POpen Grind which is recommended for modified/open class and has a target rpm of 8500 - 9000 rpm. It also says its a low lift cam with more duration for better top end power. Should have a great sounding idle down load. I also will have to upgrade the engine with 36lb valve springs, a billet rod, and a billet flywheel. In the end my goal is to build just like I posted above a full out vintage style Board Track Racer with an all out performance engine. Would be finished in a similar way to my Indian tribute cruiser I built but I might go with a different color than red.

Thing is I built my cruiser with a modified 2 stroke for right at $1,300 including s&h for parts. I also ordered some parts that ended up not being compatible so I should cut the price down some from not making those errors on my second build. So as of now my goal would be $2,500 being the price range. This would save me money in the end as the Bonneville prebuilt sells for $7,400 but I don't want to buy built I want to build my own so I can plan it out and build it how I want it from start.

 

[Frankenstein]

Can you tell me how fast you even need to go? All those mods seem a bit much, these are bicycles after all, if you had an extra hundred pounds of frame then maybe all that effort would be worth it. I'm afraid to ride a 212 unmodified let alone one that's been squeezed of all its hp.

If you want auto clutch then do it, a good one may outlast the motor, torqaverter is a torque converter but that brand specifically is essentially a ctv with 2 preset ratios, basically once the target rpm is reached and the torque against the engine is low enough the mechanism will move one set of cones apart and the other together, this bumps it into second gear which letsleyou ride out the throttle over a higher speed. My friend's last build would shift into second just under 20 mph so it is really good in the city traffic and hills while not screaming to death at 45mph (which I might add doesnt take very long to get to on a bicycle on 212ccs of steroids)

Enclose the drivetrain, you're right and it's not just professional looking, it gets the most out of your gears and chain by protecting them, and keeps your pants and shoes a lot cleaner.

 

[Rusty_S85]

Can you tell me how fast you even need to go? All those mods seem a bit much, these are bicycles after all, if you had an extra hundred pounds of frame then maybe all that effort would be worth it. I'm afraid to ride a 212 unmodified let alone one that's been squeezed of all its hp.

If you want auto clutch then do it, a good one may outlast the motor, torqaverter is a torque converter but that brand specifically is essentially a ctv with 2 preset ratios, basically once the target rpm is reached and the torque against the engine is low enough the mechanism will move one set of cones apart and the other together, this bumps it into second gear which letsleyou ride out the throttle over a higher speed. My friend's last build would shift into second just under 20 mph so it is really good in the city traffic and hills while not screaming to death at 45mph (which I might add doesnt take very long to get to on a bicycle on 212ccs of steroids)

Enclose the drivetrain, you're right and it's not just professional looking, it gets the most out of your gears and chain by protecting them, and keeps your pants and shoes a lot cleaner.

Well the springer forks that they sell for this frame is widened out to 4 1/2" ID to accept motorcycle tires.
http://sportsmanflyer.com/shop/parts/sportsman-springer-wide-glide-fork/

The frame they sell is the same frame they build their bikes with, which they ran at Bonneville and set records in the 175cc and 250cc classes at over 80 mph. The frame is designed for 100 - 250cc engines.
http://sportsmanflyer.com/shop/parts/sportsman-flyer-drop-loop-frame/

Thing is though I wont be gearing for top end. I will be gearing more for acceleration which is why I am shooting for a high rpm redline. This is supposed to be my race bike while my 2stroke chinagirl is my cruiser. My goal for the racer is to have more acceleration and a higher top end than my cruiser. So to be conservative I want to gear for a top end of around 55 mph maybe 60 mph which should be doable if they got over 80 mph out of this frame with a 175cc engine. Doesn't mean I will run it that fast though. It will have front and rear drum brakes.

 

[Frankenstein]

Well the springer forks that they sell for this frame is widened out to 4 1/2" ID to accept motorcycle tires.
http://sportsmanflyer.com/shop/parts/sportsman-springer-wide-glide-fork/

The frame they sell is the same frame they build their bikes with, which they ran at Bonneville and set records in the 175cc and 250cc classes at over 80 mph. The frame is designed for 100 - 250cc engines.
http://sportsmanflyer.com/shop/parts/sportsman-flyer-drop-loop-frame/

Thing is though I wont be gearing for top end. I will be gearing more for acceleration which is why I am shooting for a high rpm redline. This is supposed to be my race bike while my 2stroke chinagirl is my cruiser. My goal for the racer is to have more acceleration and a higher top end than my cruiser. So to be conservative I want to gear for a top end of around 55 mph maybe 60 mph which should be doable if they got over 80 mph out of this frame with a 175cc engine. Doesn't mean I will run it that fast though. It will have front and rear drum brakes.

I see, then something like a torqaverter would work well, if you load that up and keep an average sized gear or slightly smaller you could easily grab those speeds and have a really good acc rate. Like I said it I doesn't take long to get fast at 212, stock is pulling 40 in half a block which is kind of scary, I drive a truck that takes probably twice that to get there, and he's using half a much throttle (transmissions are painful to replace and somewhat expensive, I dont like abusing my machines.)

 

[Rusty_S85]

I see, then something like a torqaverter would work well, if you load that up and keep an average sized gear or slightly smaller you could easily grab those speeds and have a really good acc rate. Like I said it I doesn't take long to get fast at 212, stock is pulling 40 in half a block which is kind of scary, I drive a truck that takes probably twice that to get there, and he's using half a much throttle (transmissions are painful to replace and somewhat expensive, I dont like abusing my machines.)

lol See that's the thing. I like the pull of my 2 stroke cruiser bike. But for a race bike I want it to be a grab you by the balls acceleration. Not so insane that it wants to pull the front end up, but enough to really say I'm built for racing.

I also am looking at running this.

http://sportsmanflyer.com/shop/parts/sportsman-pedal-crank-assembly-with-reduction-hub/

Its their reduction crank assembly which is a very close reproduction of the board track racer drive system. Can only get it if you purchase a kit as well which I would. I just need to read some more on it maybe ask them if the gears are changeable or if its just the fact that you are getting a gear reduction to a smaller sprocket which means I could also run a smaller sprocket on the rear.

Plus if I can run motorcycle tires like the description says I would so buy some vintage motor cycle tires from coker. But the wheels they offer doesn't make no mention of motorcycle tires so I don't know if those are bicycle wheels or the wheels for use with motorcycle tires.

 

[CrazyDan]

Sadly motorcycle tires are illegal in the socal motorized bicycle races...

 

[Rusty_S85]

Sadly motorcycle tires are illegal in the socal motorized bicycle races...

Which works out for me because I wont be racing the bike. It will be used on the street as well as taken to local car shows.

 

[Frankenstein]

Which works out for me because I wont be racing the bike. It will be used on the street as well as taken to local car shows.

Yes, I've been thinking along those lines too, I am really sick of the flat tire crap, I really think a slightly more hard core tire would be OK, I'm fine with slower acceleration, I just want something that actually tries to resist nails and glass. I'm debating 4 inch wide rim against a 2 inch steel one that came stock, see if I get a 4 inch I might not get a beefy tire in there, I'd probably need to use a slick or very low profile, just the bike geometry. If I use the original (which it alone is a 20 inch rim, and without it even being laced onto a hub and no tire it can support my full weight without any visible flexing, something I found very impressive with the huge variety in quality of rims, imagine that was stock back then!)... Original rim I could find a very decent motorcycle or dirt bike tire that would work beautifully. Then it's just figuring out how to bulletproof the 27.5 bicycle tire upfront since there's just no motorcycle tire that large.