Thunder Power Jet

ReycleBill

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It seems the boat and snowmobile guys have known about these things for years. Even S&S offers a version for the Harley riders running S&S carbs. And perhaps I'm the last person in the world to learn about the Thunder Power Jet which according to the manufacturer, not only provides additional fuel at full throttle but also "gives you a range of over 10 to 12 jet sizes with precision external adjustment" with no tools needed.

Anybody ever use such a thing?

My riding sometimes takes me from sea level to 5,000 altitude in a single weekend. It's impossible to jet for that. Might something like this solve my problem?
 
Yeah... if I remember my history correctly, one of the main reasons CV's were designed was to make a carb that was better at altitude compensating.
 
No, Bill, you're not the last guy to learn about Thunder Products. I actually ordered one of those "Power jets" a few years ago just to have a look at it because the ad story made my bullshit detector spike (mystery scientist markets miracle performance boosters through obscure snowmobile shop, instead of selling rights to the big boys for the big bucks). The look was as far as it went. I wouldn't bet on it, but that stuff might work on a 2-stroke motor. I sure wouldn't try it on a 4-stroke.
 
Power jets are still a feature of Mikuni TMX series dedicated 2-stroke carbs, if I'm not mistaken.
 
Power jets are still a feature of Mikuni TMX series dedicated 2-stroke carbs, if I'm not mistaken.

I've also noticed that .Mikuni sells their own line of power jets that can be added to.Mikuni CV carbs.

This statement by Thunder Power Jet manufacturer also go my attention:

"With the Thunder PowerJet installed, the main jet is decreased by 20% to 25%. The remaining fuel is supplied by the Thunder PowerJet. This combination gives you great throttle response due to the smaller main jet’s superior atomization. Throttle response is dramatically increased. Overall power is also increased for several reasons. First of all, the Thunder PowerJet can be dialed in so quickly and accurately for any temperature or altitude that you no longer dread rejetting your carbs. It is about a one to two minute job. With the Thunder PowerJet, fuel distribution is enhanced because you are now adding fuel in two locations instead of just one. The last benefit is increased fuel efficiency. This is due to part throttle riding conditions where you are running on the the smaller main jet."

I'm also wondering if power jets might solve the problems caused with 2-1 intakes running a 38 round slide .Mikuni carb or other single carb.

I realize several people said that CVs are great with altitude changes but in 15 years of owning my '83XS with CV34s I have never found a jetting that would take me from Wilmington, NC. to Mount Mitchel, NC (less than 400 miles) without acting up on one end or the other.
 
The link specifies use on VM carbs, doesn't mention BS series vacuum pots. Give it a try, yours would be the first user report I've seen on a 4-stroke motorcycle application, and I might wind up eating a big plate of crow.
 
I've also noticed that .Mikuni sells their own line of power jets that can be added to.Mikuni CV carbs.

This statement by Thunder Power Jet manufacturer also go my attention:

"With the Thunder PowerJet installed, the main jet is decreased by 20% to 25%. The remaining fuel is supplied by the Thunder PowerJet. This combination gives you great throttle response due to the smaller main jet’s superior atomization. Throttle response is dramatically increased. Overall power is also increased for several reasons. First of all, the Thunder PowerJet can be dialed in so quickly and accurately for any temperature or altitude that you no longer dread rejetting your carbs. It is about a one to two minute job. With the Thunder PowerJet, fuel distribution is enhanced because you are now adding fuel in two locations instead of just one. The last benefit is increased fuel efficiency. This is due to part throttle riding conditions where you are running on the the smaller main jet."

I'm also wondering if power jets might solve the problems caused with 2-1 intakes running a 38 round slide .Mikuni carb or other single carb.

I realize several people said that CVs are great with altitude changes but in 15 years of owning my '83XS with CV34s I have never found a jetting that would take me from Wilmington, NC. to Mount Mitchel, NC (less than 400 miles) without acting up on one end or the other.
You might be off in your jetting on the CVs. I have Mikuni 38MM flatslides on my BMW R/90S and I have no carb issues going to M/M,etc. Power Jetting works from 3/4 to full throttle and I doubt you'd be traveling at the speeds on the BRP. If you want power jetting get a set of Lectron carbs(spelling).
 
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