NITROUS OXIDE ( nos / n2o ) advice forum

EXCELLENT video, you should take up that kind of work as a job.

Increasing the speed by 50% as it should be calculated from the base figure not from the top figure, would take far more than a 50% increase in power, as the power required for each extra MPH increases exponentially, so that's a SUBSTANTIAL achievement.

I'd LOVE to see the results of using any other brand of nitrous kit on such a small engine.

It would either achieve nothing due to being supplied as a gas without any extra fuel, as in the case of these Mickey mouse type set up and run out after a couple of seconds or it would MELT the engine BIG TIME.

GREAT RESULT and please keep up the GREAT work.

Sweet.

CRAPOLA! Problems do come in waves!

Looks like I'll be making my first troubleshooting video!

So I had just stepped up the jetting to the 5HP level and I went out for a ride to do some testing. I went through the usual motions and everything checked out OK. Then, I went to go for some long power passes to ensure that the engine can take the 5 HP hit. Well, I hit the button and the thing rocketed out, chugging the nitrous hit like a cheap beer.... for about 2 seconds and then went instantly LEAN and lost almost all power!

I went back home and sure enough, the fuel jet clogged up again! RATS! The jet is so tiny that ANY debris whatsoever can cause blockage, and to add to this problem, I didn't have anything small enough to poke through the jet to clean it because it's as small as a strand of wire. That's when I had a EUREKA moment and found a piece of electrical wire and poked 1 single strand into the jet. Whatever was in there was in there TIGHT! So I went to put it back in and test the flow and the damn thing clogged again after 3 pulses! AAAARGH!

I then repeated the cleaning and decided to use some degreaser on a cotton swab to clean out the pulsoid outlet. I found quite a bit of dirt, tiny bits of o-ring debris, and tiny pieces of aluminium bits from the threads of the pulsoid body. This debris must have come from the action of removing and installing the steel jet holder. So now I have to take special care to make sure I clean the pulsoid outlet before installing the jet holder.

Just be aware that using these TINY jets requires careful handling and cleaning of the system to ensure it doesn't get clogged and LEAN OUT your nitrous/fuel ratio!

The engine is still in great shape; I kept the carb slightly on the rich side in the case that this might happen and I think that might have saved it from certain doom.

After all of this crap, I found my rear tire was loose and I attempted to tigheten down the locking mechanism until it broke! CRAPOLA! Now I need to order replacement parts! AAAAACK!

I'm done for the day and I just want to relax for a while!

OK, so I couldn't leave things alone...

So I fixed my fuel jet issue AND managed to get the adjuster bolt to lock the axle, which solves the issues I've encountered today.

EXCEPT!

As I was static testing the system, I RAN OUT OF NITROUS.... NOOOOOOooooo!!!!

There's no way I'm going to service it back up with my car today. I'm going out to the movies and get some drinks afterward!

Yes it's very risky when using such small jets. That's one of the reasons I came up with my UNIQUE single metering jet location at the Pulsoid outlets for my multi-cylinder DP systems, as a single jet of say 100 HP is far less likely to get blocked than a single 25 HP jet and I've no doubt that has contributed to our outstanding reliability record.

Yea it was an annoyance to say the least. I ended up cleaning the pulsoid until it was immaculate.

It's funny because I wa ripping with this system for a while now and all of a sudden it decides to screw me right when the thing was gonna totally rip on 5HP!

I'm determined to get a 5 HP run in soon!

UPDATE TIME:

While I'm out of nitrous and awaiting a new component, I've decided to begin installing the NEW MUCH MORE POWERFUL engine and begin running it in.

This engine is a Zenoah G290 29cc, 3.5 bhp engine which is much more than the 1.2 bhp G23! This engine alone will propel me beyond 30 mph without any further changes. For nitrous, I'm backing down to 2.5 bhp because this engine has more compression and more aggressive ignition timing so I must step up the ladder all over again. The good news is that I'm still running 98 octane fuel so I should be fine for up to the 3.75 or even 5 hp jetting combos.

There are a few more changes as well:

I installed a centrifugal clutch to assist with the big drive spindles as this will allow the engine to rev up into a more appropriate range for acceleration. The direct drive setup wasn't pleasurable to ride on such a large spindle. The clutch also has a higher engagement point than stock for snappier and aggressive acceleration.

Instead of just plugging in the two lines into the airbox, I used two olive fittings and nuts to thread them into the airbox cover; this doubles as a velocity stack as it will draw more airflow into the airbox and ram it into the carburetor bore. The sealant is just some RTV to keep out any air and to keep the lines from being drawn into the box any further.

I still have more goodies for this beast, but that will come up in another update...

8.5 HP is the new short-term goal!!!

No worse feeling than running out of NOS haha. I feel your pain. Loving following this project though

HAHA, I'm not REALLY out of nitrous as I have about 17 lbs left in the bottles in my garage, but I need a servicing fitting that I can use with my U.S. shit-head fittings on my U.S. shit-head bottles. I'm too lazy to hook it up to my car to service the SFBK, and besides, I want to make a HOW-TO video on servicing the kit with nitrous.

The fittings should be with you to do the fill very soon.

No rush... I managed to aim my nitrous desires elsewhere today...

So OMG so like... yea... like I finally finished breaking in my Goped of DOOOOOOM!!! It only took like 3 months just to drink a tank of fuel

Anyway, I'm going to retard the timing on the engine and test out the 5 HP hit right off the bat. If all goes well, I'll attempt to make another video. It won't be of the same level of quality but I can only do so much with the software on my Mac.

Sweet but have you done anything to increase the clearances between the piston and the bore?

I forgot about the clearances... it's a good thing you reminded me. That's gonna have to wait because I have to machine the piston and my top concern at the moment is getting the lexus back on the road for break-in and the dyne.

Well, I decided to go ahead and test out the 5HP jetting on the new engine after retarding the ignition timing... but it didn't like it. During the static test the engine would rev up on activation of the nitrous and then die as soon as I let go of the nitrous.


Against my better judgment, I decided to just briefly hit it with the carb set even richer to compensate (I was in a remote area without extra jets). For a brief moment, the engine torque felt like it magnified 5 X's over as the front wheel lifted off the ground!!! Mind you, this was with my 190lb self leaning over the bars as far as possible, a fully serviced SFBK on the bars, a heavy lawn battery forward of the deck, and the biggest drive spindle I have!!!

After the engine cut-out, I thought I melted something but it's actually in PERFECT condition surprisingly! The jetting has been reduced to 2.5 once again.

I must admit this though: I am VERY AFRAID to ride that thing again on a 5HP hit

It's certainly worthy of being... THE GOPED OF DOOM!

Here's the video: Goped 5HP Test Fail

It was probably the differential in the delivery time of the nitrous and fuel, as it's a bigger problem with such long pipe lengths and worse when you fit bigger jets.

If you relocated the SFBK so the pipes were shorter it would probably fix that problem, but LIFT OFF would be a MUCH BIGGER problem.

Oh geez, I'm REALLY nervous about the level of power this thing is going to achieve. I was struggling for control when I felt the handle bars push into my gut when I hit it! I couldn't let go of the button because I gave the death grip to the handle bars as it lifted and since it's a thumb trigger, it was impossible for me to let go of the nitrous. It's actually a good thing that the engine quit LOL!!

Also on the way home I couldn't stop my hands from shaking as my nerves were going nuts!

I can fully understand all that and rather you than me buddy.

I'll continue testing with the 5N:5F and 7.5N:5F as I've had good results with the previous engine. I'll move the setup around in the future to shorten up the routing. I think the excess fuel in the previous settings were what gave the fuel adequate time to reach the carb with the long pipes.

Exactly right, which is how the US JUNK kits get away with it on those engines that don't blow up.

Perhaps a 7.5F would allow the flow rate to be adequate enough to match that of the 10N? Although it would be less than optimum, the acceleration would still be faster than that of the 7.5N:5F. It would buy me some time before I move the entire setup to the rear fender.

It might help the initial hit but it would adversely affect the ongoing running.