Yes, its on road engine...... but I would like to use for off road as well ( I'm thinking to reduce the EPA to 90% full throthle in my buggy ).

Thats hardly a logical thing to do. $550 USD+ for the best onroad engine in the world to be used with the throttle EPA set to 90% in the dirt???

Doesn't make any sense why u spend 35Plus21 while u can get 2 pcs of the Plus21 B5 with the same money

He use 35plus21 Onroad engine for his buggy and RB WS-7II Offroad engine for his MRX3.
Go figure LOL

Never attempted a on/rd Engine in Buggy/Truggy. The Gear ratios would be different in a off/rd VS on/rd. I know the timing is slightly different between a jp-b5n mod and a jp-r03 mod. The 35 PLUS 21 IS A Fuel hog!Most .21 on/rd Engines that i have seen don't go far on 120cc. The .21 on/rd engines don't get as good of fuel economy as the .21 off/rd engines.

Don't you want me to buy another 35 Plus 21 ?

Can I use OS plugs on my JP??

Can I us JP plugs on my OS?

I guess if someone answer your Question, They will answer my Question as well

you can but it's not wise to do so because the OS and Novarossi Turbo plug tapper is slightly different. It wont have a tight seals and might even ruined the head button. That's what I been told.

The question is WHY?

The golden word:

AVAILABILITY

now why would you wanna do that the OS taper is different and will not seal all the way, and Novarossi makes there plugs there way for a reason, would a 7.00 plug beworth a 300.00 engine
Just bust out and buy a nova plug, and i think they last longer than a os plug

Telling someone to spend on the right thing is different with drying your wallet to empty.

Yes, I know .... you are kind of love poisons you make people don't sleep. So when am I going to received it ? December okay, January is okay too.