Hawk 250 supercharger

[Weldangrind]

Originally Posted by '16 TT250

Way back when I knew little about fuels and motors I decided to put some model airplane fuel (about 50% nitro) in my Honda MB5. Those little airplane motors make a lot of power for their size so it sounded like a great plan to kick up the little bike's power. I couldn't get it to start on the kicker but with a guy helping push I eventually got it to fire. It barely ran at first but as it warmed up it seemed to be getting happier and at one point it did have some serious power. I pulled back into my parking spot and it was idling around 3K and climbing so I turned it off, the idle continued climbing-WTF? So we're staring at it and I'm starting to freak out. I pulled the plug wire thinking the switch was bad, nothing. Pulled the choke hoping to flood it, just got stronger. Luckily it was only a 50cc motor so I held the rear brake and killed it by letting the clutch out. I drained that stuff out and never tried it again.

That's the best story I've read in awhile!

['16 TT250]

As far as SC vs nos goes, we've already discussed the heat issue of a SC as well as having to figure out a pulley to drive it. Also consider the space needed. If it's a suck through system it'll probably be hard starting and likely have response issues. If blow through you'll need a fuel pump and pressure box for the carb, or a carb that can take it without a box, or fuel injection. Also consider that it takes power to run the SC so for every 1HP you get out of it you will be putting more than 1 hp of strain and heat on the engine further limiting what you can get out of it. For perspective, the SC on a top fuel car takes about 500hp to spin and it nets about 1500hp propelling the car. These are old numbers and not directly scalable, but just a thought to ponder.

The only real downside for nos is that you do have to refill the bottle whereas a SC never runs out of free air. This motor would be getting a very small shot of nos so it wouldn't cost a lot to use for occasional bursts. On one car that I ran a lot I was shooting about 100hp and would make 4-6 1/4mile passes in a day with no problem on a 10lb bottle, refills were 3.50/lb. At roughly $4 per pass it would take a lot of racing to offset the cost of a SC. I was using it quite a bit so I made my own transfer station at home with 3 different bottles to get the most I could out of each refill. The bottle can't be used to empty so there's always some left. Running a little bottle on the bike and having a standard 10# bottle to fill it with will get you a lot of run time between buying refills.

If you wanted a constant power increase like for high speed freeway cruising nos wouldn't be a good way to go, but heat would likely kill the engine under constant boost so I don't think it's a solution anyway. I had a Yamaha 650 turbo many years back and I remember feeling the engine heat on my legs when I'd run a long time under boost. In fairness I was sometimes shoving 16+psi into it, but even when I dialed it down to 12psi I could feel it and any amount of boost adds heat.

[pcspecialist]

Originally Posted by kohburn

that's only dry nitrous kits. a wet kit has jets to include fuel with the delivery.

Yes, motorcycles with no fuel pump typically use dry.

[JohnDoe2887]

Originally Posted by '16 TT250

Most nitrous systems use a fuel jet and a solenoid to allow fuel through that jet, no need to reinvent the wheel to get a controllable fuel shot with the nos shot. Most systems use a fuel pump, but it can be done with a gravity feed with the right fuel jet.

The only stuff I know of that is oxidized is nitro fuel and wouldn't get along with the carb or motor. If you went that route you'd have to jet for it and be stuck running that high $ stuff all the time, it would also get much lower MPG adding to the cost.

Way back when I knew little about fuels and motors I decided to put some model airplane fuel (about 50% nitro) in my Honda MB5. Those little airplane motors make a lot of power for their size so it sounded like a great plan to kick up the little bike's power. I couldn't get it to start on the kicker but with a guy helping push I eventually got it to fire. It barely ran at first but as it warmed up it seemed to be getting happier and at one point it did have some serious power. I pulled back into my parking spot and it was idling around 3K and climbing so I turned it off, the idle continued climbing-WTF? So we're staring at it and I'm starting to freak out. I pulled the plug wire thinking the switch was bad, nothing. Pulled the choke hoping to flood it, just got stronger. Luckily it was only a 50cc motor so I held the rear brake and killed it by letting the clutch out. I drained that stuff out and never tried it again.

Great story one of the best I have ever heard! That said you do know why that happened right? The only thing I would have done is turn off the fuel instead of flooding it. As for what happened I believe they used to call that ghosting or ghost running something like that. Any ways cause everything is being driven by belt the engine doesn't stop fireing typically it just burns the fuel in the lines.... But here my assumption is that because it was gravity fed that it kept feeding it. What you saw at first vary well could have just been fumes.... Speaking of which another thread for another day. Hey guys I am still saving up for my hawk can someone get me the carb intake measurements and the air box measurements? Thanks!! I want to start looking at my options....

[JohnDoe2887]

Originally Posted by '16 TT250

As far as SC vs nos goes, we've already discussed the heat issue of a SC as well as having to figure out a pulley to drive it. Also consider the space needed. If it's a suck through system it'll probably be hard starting and likely have response issues. If blow through you'll need a fuel pump and pressure box for the carb, or a carb that can take it without a box, or fuel injection. Also consider that it takes power to run the SC so for every 1HP you get out of it you will be putting more than 1 hp of strain and heat on the engine further limiting what you can get out of it. For perspective, the SC on a top fuel car takes about 500hp to spin and it nets about 1500hp propelling the car. These are old numbers and not directly scalable, but just a thought to ponder.

The only real downside for nos is that you do have to refill the bottle whereas a SC never runs out of free air. This motor would be getting a very small shot of nos so it wouldn't cost a lot to use for occasional bursts. On one car that I ran a lot I was shooting about 100hp and would make 4-6 1/4mile passes in a day with no problem on a 10lb bottle, refills were 3.50/lb. At roughly $4 per pass it would take a lot of racing to offset the cost of a SC. I was using it quite a bit so I made my own transfer station at home with 3 different bottles to get the most I could out of each refill. The bottle can't be used to empty so there's always some left. Running a little bottle on the bike and having a standard 10# bottle to fill it with will get you a lot of run time between buying refills.

If you wanted a constant power increase like for high speed freeway cruising nos wouldn't be a good way to go, but heat would likely kill the engine under constant boost so I don't think it's a solution anyway. I had a Yamaha 650 turbo many years back and I remember feeling the engine heat on my legs when I'd run a long time under boost. In fairness I was sometimes shoving 16+psi into it, but even when I dialed it down to 12psi I could feel it and any amount of boost adds heat.

There are other ways to shead heat then just radiation.... I think it's worth exploring other options, as apposed to the old radiator and coolant path....

[Ariel Red Hunter]

Originally Posted by JohnDoe2887

Great story one of the best I have ever heard! That said you do know why that happened right? The only thing I would have done is turn off the fuel instead of flooding it. As for what happened I believe they used to call that ghosting or ghost running something like that. Any ways cause everything is being driven by belt the engine doesn't stop fireing typically it just burns the fuel in the lines.... But here my assumption is that because it was gravity fed that it kept feeding it. What you saw at first vary well could have just been fumes.... Speaking of which another thread for another day. Hey guys I am still saving up for my hawk can someone get me the carb intake measurements and the air box measurements? Thanks!! I want to start looking at my options....

Ghost running, hmm. Is that related to the old saw "There'll always be an England, because the engines keep running on!!".

[JohnDoe2887]

Originally Posted by Ariel Red Hunter

Ghost running, hmm. Is that related to the old saw "There'll always be an England, because the engines keep running on!!".

https://en.m.wikipedia.org/wiki/Dieseling
I thing ghosting is slang.... The heat from his engine was most likely the cause of his continued firing....

[jimwildman]

Originally Posted by '16 TT250

As far as SC vs nos goes, we've already discussed the heat issue of a SC as well as having to figure out a pulley to drive it. Also consider the space needed. If it's a suck through system it'll probably be hard starting and likely have response issues. If blow through you'll need a fuel pump and pressure box for the carb, or a carb that can take it without a box, or fuel injection. Also consider that it takes power to run the SC so for every 1HP you get out of it you will be putting more than 1 hp of strain and heat on the engine further limiting what you can get out of it. For perspective, the SC on a top fuel car takes about 500hp to spin and it nets about 1500hp propelling the car. These are old numbers and not directly scalable, but just a thought to ponder.

The only real downside for nos is that you do have to refill the bottle whereas a SC never runs out of free air. This motor would be getting a very small shot of nos so it wouldn't cost a lot to use for occasional bursts. On one car that I ran a lot I was shooting about 100hp and would make 4-6 1/4mile passes in a day with no problem on a 10lb bottle, refills were 3.50/lb. At roughly $4 per pass it would take a lot of racing to offset the cost of a SC. I was using it quite a bit so I made my own transfer station at home with 3 different bottles to get the most I could out of each refill. The bottle can't be used to empty so there's always some left. Running a little bottle on the bike and having a standard 10# bottle to fill it with will get you a lot of run time between buying refills.

If you wanted a constant power increase like for high speed freeway cruising nos wouldn't be a good way to go, but heat would likely kill the engine under constant boost so I don't think it's a solution anyway. I had a Yamaha 650 turbo many years back and I remember feeling the engine heat on my legs when I'd run a long time under boost. In fairness I was sometimes shoving 16+psi into it, but even when I dialed it down to 12psi I could feel it and any amount of boost adds heat.

for a decent accross the board gain just eliminate the cat. it's probly full of lead anyway.

you need a welder to do it , cut out the section of pipe with the honeycomb in it and replace it with a meduim walled pipe of similiar diameter..

some porting of the weld imside the pipe at the flange area wouldnt hurt either.

[JohnDoe2887]

Originally Posted by jimwildman

for a decent accross the board gain just eliminate the cat. it's probly full of lead anyway.

you need a welder to do it , cut out the section of pipe with the honeycomb in it and replace it with a meduim walled pipe of similiar diameter..

some porting of the weld imside the pipe at the flange area wouldnt hurt either.

If I was to go as far as to port the head I would just buy a 3D printer and make a new one.... (Send it off to be metal casted of course....)

[MDStroup]

https://www.monoprice.com/product?p_id=13860

www.raspberrypi.org/products/pi-zero/

Just a heads up. If you really want to use a single board computer to make an ECU, do use the Chinese knock off(that is ironic on this forum). They had really spotty quality. Go with the RaspberryPI Zero. It is just under the power of a RaspberryPi 2 but it only costs $5.


Also if you are serious about the 3D printing look at the monoprice select V2. It is a rebranded Wanhao duplicator i3 V2 so it uses all of the same upgrades. An you can pick them up all day at $350. Even better, monoprice runs a 20% off discount every once in a while so you can get it for only $300 shipped to your house!

Sorry the links are so funny. I am on a tablet so it is hard to copy and paste. I can fix it when i am able to get on a computer.

[MDStroup]

http://www.reddit.comr3Dprintingcomm..._what_are_the/


Here is a link to so great upgrades for the Wanhao duplicator i3 V2/Monoprice select v2

[MDStroup]

Also, if you want a little boost in power why dont you put on the munki 30mm carb( not the 26mm that some people have put on) and the Pro Circuit T4 exhaust for the Honda CRF230f? It was already shown in a thread about an exhaust for the Hawk 250 in a video that the T4 exhaust nets about 5hp on a 200cc bashsan bike.

['16 TT250]

Originally Posted by JohnDoe2887

Great story one of the best I have ever heard! That said you do know why that happened right? The only thing I would have done is turn off the fuel instead of flooding it. As for what happened I believe they used to call that ghosting or ghost running something like that. Any ways cause everything is being driven by belt the engine doesn't stop fireing typically it just burns the fuel in the lines.... But here my assumption is that because it was gravity fed that it kept feeding it. What you saw at first vary well could have just been fumes.... Speaking of which another thread for another day. Hey guys I am still saving up for my hawk can someone get me the carb intake measurements and the air box measurements? Thanks!! I want to start looking at my options....

I know exactly what happened, this fuel is compression ignited like diesel fuel so once the combustion chamber got hot enough it kept running. Closing the fuel valve would have meant waiting for the carb to empty and it was already heading towards 10K RPM when I killed it. Top fuel cars, which also run nitromethane, run without spark after about half track since the plugs are toast by then. They shut the fuel off to shut the engine off and since they're injected the fuel flow stops right away.

Never heard of ghost running and no clue what belt you're talking about, there's no belt on that bike nor most other bikes. What fumes? You might be hitting the pipe a bit too much and the smoke has clouded your thoughts.

[JohnDoe2887]

Originally Posted by '16 TT250

I know exactly what happened, this fuel is compression ignited like diesel fuel so once the combustion chamber got hot enough it kept running. Closing the fuel valve would have meant waiting for the carb to empty and it was already heading towards 10K RPM when I killed it. Top fuel cars, which also run nitromethane, run without spark after about half track since the plugs are toast by then. They shut the fuel off to shut the engine off and since they're injected the fuel flow stops right away.

Never heard of ghost running and no clue what belt you're talking about, there's no belt on that bike nor most other bikes. What fumes? You might be hitting the pipe a bit too much and the smoke has clouded your thoughts.

I first read about that on a forum so yea.... And there if I remember correctly they were talking about old fords that wouldn't stop when turned off that was when I was like 11/12 I don't remember the details.... I do remember it was when I first started to get into motors and cars.... A had a cluster f@$k of mind thoughts there.... =P

[Ariel Red Hunter]

Originally Posted by JohnDoe2887

I first read about that on a forum so yea.... And there if I remember correctly they were talking about old fords that wouldn't stop when turned off that was when I was like 11/12 I don't remember the details.... I do remember it was when I first started to get into motors and cars.... A had a cluster f@$k of mind thoughts there.... =P

If you read that link that was posted on "Dieseling - - - ", one of the last lines explains why too lean running can cause dieseling, also known as "running on" and maybe even the term I've never heard before "ghost running." And I don't think I am the only one who thinks these engines are set up too lean at the factory.