NITROUS OXIDE ( nos / n2o ) advice forum

Then it's time to move the system to the rear fender!

LOL don't you ever sleep?

Not if I can help it!

That should do the trick and yes I'm betting a Minimiax will be needed assuming the piston doesn't seize with so much extra power/heat.

BTW I seem to remember some mention of you sending me your piston to mod but I don't remember answering you on that. The best thing to do is send me a pic of it first (so I can see if we can hold it on our lathe), before we do anything else.

Yes, you did answer me via email about that. The piston is 36mm in diameter so it is quite small. Here is a link to the replacement part. http://www.davesmotors.com/zenoah-574791001-piston-36mm-g290rc-fg-07808.html

And fear not, I won't be using any prolonged hits of the juice until this is done. I'm also going to reduce the compression somewhat by using a thicker cylinder gasket.

That's fine and I should be able to handle that, so if you want to send it over (or maybe I could locate one here and save that international postage), I'll machine that down for you.

Lowering the compression should help and it would also help if you could widen the exhaust port (if it can take it) and possible increase the height of it a little. You should certainly be able to open it up downwards by the amount you raise the cylinder by at least if not more, depending on how well matched they are as standard.

BTW I was a very successful 2 stroke tuner prior to getting addicted to nitrous.

You might also like to add a water injection system to the Go Ped, as that would help cool the piston and bore to prevent seizures.

You could use a gravity fed water supply but it wouldn't atomise very well, so I've just had a GREAT idea that might solve that. If you used a small bottle of fizzy water, you could shake it up before use and that would provide some pressure to deliver the water (so no need for a pump) and if we used one of our atomising nozzles, the pressure MIGHT be adequate to atomise it.
The only concern I have about this is how much water it would supply even with our smallest nozzle, as it might just drown it.
You could use a generic solenoid to control the flow, so all you'd need from me would be one of our nozzles and possibly some pipe etc.

LOL BRILLIANT IDEA!!!

You know I have plenty of generic solenoids at my disposal and plenty of nylon pipe! I would love to try this! Along with the nozzle, I'll be needed some more olives as I used my last two last night with the relocation of the SFBK.

Also, remember that I DO have and alcohol carb for this engine!

Switching to alky alone would almost certainly solve the expansion/seizing problem and you may not even need to mod the piston for extra clearance as alky motors run MUCH COOLER than petrol motors.

So true...

On the other hand, it would be a great learning experience to get this W/I idea to work!

Agreed

Okay, Trev, here's the scoop: the engine is still cutting out as soon as the nitrous is deactivated. I was doing the static tests as I have before on the previous engine and that one worked exactly as it should except for this one.

Now I've removed the carb needle settings out because they made no difference. However, I noticed that the butane fuel CONTINUES to enter the carb AFTER the pulsoid has closed. I found that the butane liquid evaporates so slowly, that the remaining amount inside the pipe continues to boil and enter the carb LONG after the nitrous is cut out. That is why the engine continued to die out even while I tried to open the carb all they way ,which didn't help anything anyway because the carb continues to deliver fuel with every piston stroke.

But then, why did the previous engine continue to run properly with the same issue? I can only suspect that the INJECTION POINT has something to do with it. I say this because in this setup, the nitrous and fuel spray directly into the carb, while the previous setup had the nitrous and fuel FOG the airbox, which allowed the fuel to dissipate into the airbox in a controlled manner and not down the carb throat directly.

Of course, this is all speculation, I'll have to experiment by swapping airboxes and routing the lines like they were before.

I had considered and expected that (the lag in the fuel delivery), to be at least a contributory factor, so I'm confident that will be the case and your opinion of the injection point makes sense as well.

It really is the only factor that I can think of that's causing the stall out. I tried routing the lines outside the box where air goes in, however I haven't been successful and my plug has fouled out too many times that I just became frustrated. The nitrous line is also too aggressive and caused a small backfire because I tried keeping the nitrous untouched and the fuel facing one of the air inlets but that didn't help. The last test I want to conduct is the actual swapping of the entire airbox that the previous setup had.

I'm not happy


I'll try again in an hour... I'm letting the plug and crank case dry out a little.

ACK!!! FRUSTRATION!!!

I swapped the intake airboxes and set the whole thing up EXACTLY as with the previous engine and the same problem remains!

However, there are still avenues to travel...

1) I restore the timing to the position it was as STOCK, except that I doubt it is the cause of the problem but it is a possibility.

2) Airleaks from seals being blown out from the backfires I've suffered.

3) Both 1 & 2.

I just checked the carb diaphram to ensure that it didn't suffer damage during a backfire and it was all good. Looking at the rear seal looked good too. I still need to check the front seal but the cylinder gasket and crankcase gasket also look good..

I did find some garbage in the carb filter screen so I cleaned that out as well. But so far all looks good.

I may have to use the old engine again while this one is inoperable.

The seals of the engine are perfectly intact.

I'll try the other engine, but I needs some tooling to transfer the clutch assembly so it may take some time.

I also have to investigate the fuel supply. Perhaps there is an abnormality there.


I WILL FIND A SOLUTION!!!

I wouldn't expect it to be anything major, try it again on a smaller dose and if that works OK it MUST just be down to the amount of fuel overrun that the engine just can't move quick enough to keep running.

That's just it, I'm using the smallest jetting possible to static test and it's the same combination I used on the first engine. The first one worked well with the 5n:5F and 7.5N:5F on both the static and the road tests. This one keeps dying no matter if I used 10N:5F 7.5N:5F or 5N:5F (the current jetting)...

I will try some fresh fuel and make sure the fuel filter hasn't disintigrated.

While I continue my troubleshooting, I wanted to share my new on-board cam view for future videos.

I like this angle because you can see the nitrous lines, the injection point, the action of the carb, engine, the exhaust smoke, and relative speed of the road. And I think one of the coolest things would be the freezing of the nitrous line as the nitrous flows through it, so viewers will know that the nitrous is working. Also, viewers can see the servicing of the system whether it's changing jets, carb adjustments, bottle changes, etc.




And I think the cause of my woes (or at least a contributor) is the internal filter screen INSIDE the carb was full of junk (it looks like from the fuel filter in the tank) and could be causing the erratic performance. I'll reset the carb and tune the engine and then retest the nitrous. If all goes well, then I'll continue to step up to the 5HP hit mark even if I have to switch to the alcohol carb that I just finished prepping for this engine.