40 MPH Club

People have used rocket assist before, the only thing about that is you gotta get the amount of fuel just right or it may keep going a little (or a lot) longer than expected with no way to shut it off.... Just imagine a 1000 lb thrust solid rocket motor and trying to figure on the math to get a 300lb object up to 30 or 40mph then run out of fuel Burn time for a 0 to 30mph pull at 3.3 g's... maybe 2/10 second or less... lol

More realistically tho, something like this could be used to get it up into it's powerband... I think this engine puts out a rather modest 22 lb thrust but it's definitely doing it's job... https://www.youtube.com/watch?v=_GlocFzRqQw
 
Davezilla said:
People have used rocket assist before, the only thing about that is you gotta get the amount of fuel just right or it may keep going a little (or a lot) longer than expected with no way to shut it off.... Just imagine a 1000 lb thrust solid rocket motor and trying to figure on the math to get a 300lb object up to 30 or 40mph then run out of fuel Burn time for a 0 to 30mph pull at 3.3 g's... maybe 2/10 second or less... lol

More realistically tho, something like this could be used to get it up into it's powerband... I think this engine puts out a rather modest 22 lb thrust but it's definitely doing it's job... https://www.youtube.com/watch?v=_GlocFzRqQw
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This sounds familiar.
Seems I recall an urban legend about a guy, a Chevy Impala and a Surplus JATO bottle.

http://www.snopes.com/autos/dream/jato.asp

Tom
 
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Sorry guys, I can't get the phone to attach a battle mountain link or upload a few new pics I took of my bike. I will get on the computer tomorrow and get them on here. I did go for a short ride this morning with the GPS taped to my stem. I saw a touch over 43mph but I am pretty sure the road had a slight downward slope so I won't count it. Ahhhh the never ending quest for speed ha ha. I have been living for each day off and time with the bike. I really need to do some cosmetics and shorten the throttle and clutch cables. I wanted this bike to look nice also but have only been able to work on tuning and reliability so far. I wish i could quit my job and just do this.
 
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Just got a better look at your bike LSR, I was looking at those fixes online today, they have the perfect frame for these engines, I have one I been mtinkering with a little and I think I may sell another one of my bikes and build it up for myself.

If I ever have time I'd like to build one with 24" wheels, disc brake on front and a shift kit driving a nexus 3 speed hub in a 24" wheel,. I just think that would make a nice bike for hitting g the road for so good long road trips.

I like you bike LandSpeedRecord, keep up the good work.
 
I agree... good job on the build... now the fun part begins... riding it and tuning it in the never ending quest for more speed...
 
The old trusty Garmin Edge 305. I will figure out how to get a film clip with the GPS visible. Accelerated past 40 today and had a touch more but was not in a good place for it. I am going to order at least a 36 tooth next check, I know this thing is really winding out with the 44 tooth and I don't want to throw the connecting rod out on the street just yet.

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LandSpeedRecord said:
The old trusty Garmin Edge 305. I will figure out how to get a film clip with the GPS visible. Accelerated past 40 today and had a touch more but was not in a good place for it. I am going to order at least a 36 tooth next check, I know this thing is really winding out with the 44 tooth and I don't want to throw the connecting rod out on the street just yet.

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you'll like the 36T

you'll notice loss on the very bottom but all mine still pull hills good when i am up to speed wyen i start up them and it makes the upper cruise speeds much more comfortable.

the engine spins nice in the 30's with a 36 on the rear and doesn't rev nearly as bad at 40mph
 
Yup... I get the same things going thru my mind when the engine is wound up that high.... just the thought it can grenade at any moment if any part of the rotating assembly isn't just right... luckily mine runs exceptionally smooth, but even a small stress crack in the wrong place could have me pedaling back to the shop... I'm thinking more about going up to a 40 tooth just to load the engine up a little more at speed without compromising too much acceleration.
Keep us posted on how it does with the 36 tooth, that should be enough to load up the engine at speed enough where wind resistance may be what limits the bike and lets you run 40+ at a much lower rpm
 
Yeah but the 44t rocks on a modded motor.
However, I agree though, if your after a cruising at 40 sort of thing, go the smaller sprocket. I'm not sure how long mines going to hold together when it's hitting 10G either, lol.
 
Yup... nothing like having a decent top speed and plenty enough acceleration to get there quickly... if I do put on a smaller sprocket it'll be a 40 or maybe a 42... I personally don't want to go smaller than a 40 since my riding is mostly short trips on flat pavement. I'm also still running a stock nt carb but planning on a 20 mm mikuni or that 20mm Tilly I got if I ever get the time to make the adapter to run it. That'll give me even more top speed with more acceleration in the midrange on up.
 
i rarely ride in town, most of my riding is on open road shoulder or Farm to Market county roads so a 36 is perfect for me on a 26 wheel and i run a 30 on a 24 wheel, none of my engine turn 10k rpm

my bikes will hit top speed from start in about 60-75yds probably and when i do ride in town i can run right with most vehicle from light to light with about the same acceleration as most car do on average.

i have thought about trying a 40 on one of my bikes just to see how much difference it would make in pull and top speed, but honestly the 36 does such a great job for my kind of riding I dont know if I want to loose an6 top end just to gain a small amount of grunt down low.
 
My all out speed goal is really high for Bonneville. I really only ride it to test and learn the tuning. I have a safe place to test close by I just didn't go that way last ride to try out a different route. I am anxious to start trying some big gears and see what it will pull the way I have it. Definitly rpm is the limiting factor right now, I just don't know by how much. I am pretty sure it will rev out the 36 tooth and I am hunting some smaller ones that will bolt to my set up. Time, money, and work haha.
 
I do have a really steep hill on the way home if I take a certain road. It pulls really well up the steep part and is doing over 30 at the top of it so the power is probably already better than I think. It's a little tough to judge since my last GSXR race bike had 105hp at the rear wheel. This is very different.
 
It sounds to me like you're definitely reving out and the max rpm is your limiting factor for more top speed like me and if it can climb a fairly steep hill without losing too much speed or maintaining a certain speed, the power is there and a gear change will definitely get you faster...
I have a small pocketbike CVT I bought last summer but my frame is too small to get it in there and working the way I'd like it to, but maybe in one of my next builds I'll get a bike with a larger frame so I can run it thru a jack shaft behind or under the engine, it will also need to be modified and a new plate made for it to make it narrower as well as upgrading the bearings but it would offer enough range to install a 36 tooth and accelerate like the 44 on the bottom but top out like a 32 tooth since it's about 10% overdriven at full speed.
Getting this to work on a CG setup won't be an easy task but if I can find the right frame or chop up and re weld a frame I should be able to get it to work.
 
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