Dry NOS ped

[schroeder]

Here's my Dry NOS-ped.

[SprtMstr77]

sick man, can u tell me the pro's and con's of a dry nos ped. has it siezed up yet??

[Stuntfoot24]

WTF! what is up with those tires?!

[schroeder]

dry NOS system and tires

The jet in my dry system is very tiny, and one that I had to make as that NOS doesn't sell one as small. My set up has proven to be very safe for the bottom end acceleration. I've had it for about five years or so on a few different set ups. The lower rpm range is when the carburetor is in a rich condition, so this is when a dry system is useful. The piston can melt down if used recklessly on the top end at close to maximum rpm as that this is when the engine is operating in it's most lean condition. It is very tempting to tap the nitrous oxide button a full speed for a hint of a zing, but I have melted down a few motors doing it. For using the NOS dry system with a pipe it must be used after the pipe comes on. Using it before will cause the engine to bog. With an exhaust can however you can unload the nitrous oxide even from lower speeds and it just pull right on through. It's a blast.

The piston on the left in this picture was still hanging in there after 3 tanks of nitrous and several tanks of fuel. It also endured the displayed dyno run. The particular dyno used is a type which puts a load on the motor instead of relying on inertia.

Here's the basic system that I use


The tires were from Arizona Jet Ski.

[SprtMstr77]

so basically wat ur saying is if i use it like u said i will b ok and my engine wont sieze?? cuz i might get 1 next month.

[schroeder]

be safe

Originally posted by SprtMstr77
so basically wat ur saying is if i use it like u said i will b ok and my engine wont sieze?? cuz i might get 1 next month.

What it comes down to is nitrous oxide accelerates the burn of fuel so you can add extra fuel. If you don't have extra fuel to use when the nitrous oxide enters the engine the engine will be prone to seizure. There're are many variables resulting in needed experimentation, but the largest safeguards to dependability are the tiniest nitrous oxide jet possible and a rich fuel condition when the nitrous oxide is being used. Make sure you get more fuel than you need to begin and then go backwards. If you start out with a lean fuel condition, most likely you'll roast some pistons and cylinders.

You don't need to go big on the nitrous oxide jet with this dry NOS system, just big enough to use a little extra fuel to stay slightly ahead of the next guy.

[SprtMstr77]

um i didnt understand that lol. but i think u said i need 2 tune a lil rich if i get nitrous??

[streetped]

Originally posted by SprtMstr77
um i didnt understand that lol. but i think u said i need 2 tune a lil rich if i get nitrous??

yea u need to run richer nitrous shrinks the fuela nd pushes more through meaning u need to have more to push through like he said so when u hit the nitrous it will lean out some and if u are already lean when u hit it, well it could have bad results, and expensive ones at that

[njgangster]

thats pretty hot hot i am thinking of buying a dry nos kit for my goped ped but i dont wanna be goin through top ends every month

[schroeder]

piston dependability

If you set up the system with a very modest sized jet, and use it for the bottom end acceleration, you can use the dry nitrous oxide system all day long. The problem is it's hard to keep the finger off the button on the top end because it's fun. That will melt pistons quickly with the dry system.

Part of dependability stems from the piston set up. For my piston tiny lubricant holes are drilled in the piston which run up and down just outside the exhaust port, but not into the transfers. I also grind tiny dimples just below the ring at the exhaust port location. There are also some coatings which can be applied to the piston which will reflect heat and reduce friction, but that can bet a bit expensive.

I'm not aware of a jet that NOS sells which is as small as the one I use. I made mine by buying a blank jet with no hole drilled. I then drilled my own jet by starting with a #70 drill bit(or about that size), but didn't drill quite all the way though. The opposite side of the jet was then sanded until the tiniest amount of light could be seen when the sanded location met the tip of the hole made by the bit from the other side.

It's not the biggest kick in the pants, but noticeable and fun.

[BaG oF LuNcH 3]

Rims

Are those chrome Rims?

[schroeder]

Re: Rims

Originally posted by BaG oF LuNcH 3
Are those chrome Rims?

They're just from billet aluminum. I got them from Arizona Jet Ski.

[SprtMstr77]

if i got a wet system could i hold it down at top speed and add top speed?

[schroeder]

wet has potential for more HP and RPM

Yes, a wet system has the potential to add top speed because you'll be getting more fuel into the combustion dome. You'll be able to use that extra fuel because of the addition of nitrous oxide. The jetting between nitrous oxide and fuel needs to be dialed in.

I run a little rich and tap the dry nitrous oxide button on the top end now and again. It hits about 17,850 with a .720 spindle and me, 190lb rider. That's about 37 or 38 mph.

Remember the harder you run these little engines the more they are going to be prone to failure.

[schroeder]

budget for pistons and cylinders

Originally posted by SprtMstr77
if i got a wet system could i hold it down at top speed and add top speed?

Also, if you've never worked with a NOS system on a ped, and you have no way of testing head or exhaust port temperatures, make sure you have a budget for getting new cylinders and pistons. Always be prepared for that piston to stick when ridding.