Trinity Cv Single Carb System

[03shee2003]

does the cv system work. i cant see why one carb that is 33 mm. could replace two 26 mm. carbs. and if it is better with the one larger carb. then why do they suggest to use dual 33 or 35mm carbs for the higher horse power engines.? has anyone on this site personaly tried the cv system with 33mm carb. (not the 35mm)?i would like to know so i can decide to get one. the more replys from anyone who has tried this carb. set up would realy help me to decide if it is worth it. thanks.

[Travis's Banshee]

Ran the Trinity system on my 1st banshee. Once it was jetted I never touched it again. This system is awesome. As soon as there is a spare $450 laying around I'll put it one the new shee.

[grounded]

Yes, it works, proved it at the hill a few weeks ago

[Aussie Quad Racer]

Of coarse its gona work but the question is is it better than the twins? And at what points in the power curve are they better(or worse)?

 

You really need a stock bike, run it on the dyno then swap to the cv and run it. Compare charts.

 

Then a bike with pipes and filter. Same thing one run with twin 26 and one with the cv and one with 33-35mm twins this time too.

 

Then bike with porting and the rest of the shit and try the 3 different carbs on em.

[cgamla]

I run a Trinity 33 system on my bike. I have FMF pipes and silencers inginition advanced 2 degrees and 20 cc domes in a ADA head. The first thing I can tell you is that it is nice to have bottom end on a banshee. I won't say that it pulls like a dragster right off idle but it is so much stronger that I no longer find my self winging the clutch or shifting down all the time. If I had it to do over again the CV 33 system would be the first thing I ever did to my quad. Jetting is so easy it makes me giddy to see a cold front roll in. It takes less that 45 seconds to remove my carb and put it on a bench. All that clutter crap is gone. Also I notice an increase in gas mileage. I never really wanted bottom end but I am glad to have it. One other good thing is that if you want to just stick it in 2nd and roll through the woods the bike doesn't load up and stutter or foul plugs so whenI am giving my two year old a ride things are easier. I currently have stock clutch springs and my clutch slips just about the time the power comes on in sixth gear but my trail tech computer gives me a top speed of 75.6 mph. This would easily improve by 10 to 15 mph if the damn thing would pull sixth. Down side? I would say that I lost the last 10% of the very most extreme absolutely highest part of my top end. I never really held it open until it screamed for mercy anyways and the bike is so much easier to ride now that I couldn't give a crap less. Oh and by the way no more fighting carb boots!!!!

[cgamla]

Just for kicks I ran some numbers on surface area of 26, 33, and 35 mm holes. It is pretty interesting. A stock shee with dual 26mm mixers has a combined surface area of 1061 square mm's A single 33 mm carb has surface area of 854.86 mm's . And a 35 mm carb bore has a surface area of 961.62 square mms With the 35 mm carb your give up 100 square mm's. So

2*26=1061

33=854.86

35=961.62

 

Not enough to worry about unless you run drags for a living.

[BamaBanshee]

dude it does not work like that, with the 28's you have 28mm worth for each cyl. and that is it, the CV "constant velocity" gives your either 33 or 35 for EACH cyl.

mathmatically you are correct but your analogy does not work for this situation.

i AM NOT bashing you or your what you said, i'm simply trying to make a point so people are not mis-lead,

 

if what i have said does not make since please tell me and i will TRY to elaborate more

 

and for what it is worth i have the single 35mm and i would never go back to the stock setup, if i get a drag port i will buy another one and run dual 35s but i WOULD NOT go back to the stock dual 28 mikuni's i have 2 28mm keheins i've been dying to try but have not had the time. for my current application of cruising around the woods, and short and steep hill climbs i'd rather have the better bottom end of the CV system then the balls to the wall top speed which i would never get to due to the lack of complet strait and flat wide open space.

[cgamla]

Ok so now I'm confused. First of all he asked about the difference between a 2 carb set up and a single carb set up. Secondly he asked about two 26 mm carbs versus one 33 or 35. True the stockers may be 28mm I dont remember but you could figure the math on that too.Thirdly I have no idea how these carb setups are referred to as "constant velocity". True constant velocity carbs use vacumn and pressure differentials to move the throttle valve via a diaphragm. In a CV carb there is no cable hooked up to the throttle valve. The idea is that the velocity of air travelling through the carb always remains close to the same. This design alleviates loading and leaning during large throttle changes. Take a look at a CV carb like an SU on an older Triumph or MG automobile. I personally think Trinity decided to use the the CV designation because they theorize that with one carb either one cylinder or the other is always on the intake stroke resulting in a constant intake nonfluctuating stream, not one that is stopping and accelerating in rhythm with a single cylinder. In this case they are correct but labeling it a CV carb is misleading. Lastly you are right to say that it doesen't work like that because in the stock set up the carbs really arn't doing crap during the power and exhaust portion of the engine cycle.

[frocashmoney24]

allrgiht, 2 26's are harder to push down the throttle, they dont respond as good, and its a pain in the ass to mess with jetting in each one then get them sycronized, the 33 2-1 is great, it looks nice, easy to jet and gives you alot of snap with the throttle, top end is allright, the 2's will do alllital better on the top, if your ported and alot of stuff on your quad run a 35 , other wise mild bolt ons run a 33, nough said

[cgamla]

nuf sed really? What if we said it all then what would we do?

[frocashmoney24]

say nough said again

[03shee2003]

thanks for all the great replies. keep them coming.

[evil]

yeah they work,,,,,,nuff said

[Fireman-hott]

I thought the CV stood for Constant Vacuum.

Either way, a CV carb is about as close to Fuel Injection as you can get with a carb plain and simple.

 

At 6000 RPM the stock run about 10 horses less than the CV system.

at about 9000/9500 they level out.

You will notice the difference. The guys at the dealership told me I was ignorant for using a single carb its bad news, I showed them some dynos when I went in looking for a 40mm carb. Shut the guy right up and told him he needed to rethink the bullshit he spews.

 

My opinion get it,pipes,and a domed head and you'll stomp most of the competion 4-strokes, the 450 wil be your biggest challenge to take. I've both beaten one and been beat by one, different mods on both.

[909]

The C.V. refers to "Constant Velocity" and is referring to the intake manifold, not implying the carb is a C.V. unit. A C.V. carb on a bike can be seen clearly as such by the flat round housing on the top. The throttle cable opens up a butterfly that allows more air to pass through the mouth of the carb and the bladder living in that housing up top actually moves the slide within the carb to regulate actual air/fuel flow based on manifold vacuum. This has nothing to do with this conversation though, just some info.

 

The reference earlier to the twin carbs not doing anything in the power/exhaust stroke portion is true to a point. You have to remember that each cylinder will only be fed 28mm of air/fuel in a stock setup. The cylinders are 180 degrees apart, meaning only 1 will pull fuel at a given time. When the cylinder fires and blows out the burned fuel, the other cylinder being 180 degrees out will be pulling its air/fuel. This simply means there is 33 or 35mm (They have both available in the kits) of carb feeding both cylinders, only 1 at a time though. This will remain true up to a point where the extra angle of the intake manifold will restrict some of the flow compared to a straighter shot of 2 carbs. This is why people report a marginal loss at the very top end of their RPM range. In short, yes it works. If you'll be duning, MXing, Woods or trail riding, it will be very beneficial and much easier to maintain. If you're drag racing, you'll be better off with a PRECICELY tuned big dual carb setup.