Putting Stock Tri-z Air boot on 38mm Carb

[Just-Tri-It]

Has anyone been able to use the stock air duct boot on a larger carb for the Z like the keihin 38 or do you have to go with a slide on type filter. I know the carb is bigger just wondering if someone has found a boot off another bike that would work so you could still use the stock air set up.
Thanks

[tri-Z ripper]

yes i have a keihn 38 on the stock boot its a P.I.T.A to get on make sure the boot is warm hair dryer or heat gun and dont forget the clamp! its easier when you have 2 people to do it once you get it on it likes to push itself off! i'm telling you it can be done. its just not easy!

[the otha tri-z]

I had a 38mm on mine as well. Just drop the boot in some boiling water. It took a few tries but I finally got it to go on.

[Bryan Raffa]

I have a 39 on mine heat it up with no clamp on it.... right on the bike... heat gun ,, and have also used a torch..but careful ,, I dont recommend that.. sprock has larger intakes that accept these ,without the boost bottle... hope these guys start makin stuff again...

[Just-Tri-It]

I have a 39 on mine heat it up with no clamp on it.... right on the bike... heat gun ,, and have also used a torch..but careful ,, I dont recommend that.. sprock has larger intakes that accept these ,without the boost bottle... hope these guys start makin stuff again...

But it's the other end of the carb that I will try that on...where the air boot from the snorkel fits the back side of the carb. that elbow joint. Thanks for the insight.

[Mosh]

Measure the carb O.D. at the intake side flange.
Measure the distance between the frame or nearest obstruction.
Call UNI. Get a Pod filter with a 45 degree boot and tell them waht you carb diamter is..
I think the filter is 3.5 inches long. You have to trim the rubber boot off the filter about 1.5 inches. ( but mock it up first)
Then mount the filter so it kicks up where the coolant bottle goes.
Relocate the coolant bottle, throw on a Outerwear,and call it done.
That is what I did.
The filter sits right up under the front of the rear plastic when done.

Using a bigger carb with the stock restrictive intake system is counter productive.

[Tri-Z 250]

I have a steam shark...it works perfect for this application. The boiling works but depending on the walk to the garage it sometimes looses the heat and gets stiff again. If those guys never made another part it will only add value to the rareness of what you already have from them.

[MTS]

i got the stock Elbow on my 39mm pwk...just took a few min's of working with. it was a nice one i guess..??

[Bryan Raffa]

I use 85 elbow and 85 air tube ,, no problem.. just get a bigger clamp.. Never tryed to use the 86 air tube and that short hard rubber peice.. what parts are you useing?

[Just-Tri-It]

Measure the carb O.D. at the intake side flange.
Measure the distance between the frame or nearest obstruction.
Call UNI. Get a Pod filter with a 45 degree boot and tell them waht you carb diamter is..
I think the filter is 3.5 inches long. You have to trim the rubber boot off the filter about 1.5 inches. ( but mock it up first)
Then mount the filter so it kicks up where the coolant bottle goes.
Relocate the coolant bottle, throw on a Outerwear,and call it done.
That is what I did.
The filter sits right up under the front of the rear plastic when done.

"""Using a bigger carb with the stock restrictive intake system is counter productive.

""

It's counter productive if you leave the duct work stock but adding a lid with holes should increase the air flow significantly to take care of the 38 shouldn't it. I could keep carb and filter cleaner this way.
Thanks

[Mosh]

If you were dealing with a straighter flow intake system like a 250R, I feel that it would be fine.
But look at the shear amount of bends, and elbows in the Z intake system.
That air flow has to travel quite some distance around bends and corners to reach the carb. That will slow down air flow.
That sytem was designed simply because they had no where else to fit the airbox with the tank in the way.
It is one of the reasons the Z suffered in performance vs the other 2 sport models.
Plus that system was designed to feed the smaller stock carb.
Look at it this way.
If you were going to siphon gas with a hose, would it be easier to draw a vacumn on 3 feet of hose or 20 feet of hose?

The 20 feet would be harder simply because there is more air space to overcome.
But you can run it that way,and you are right it is better for keeping the filter clean.

I am sure that any gains lost will be minor by running the system with the bigger carb, but side by side would be noticeable.

Plus in earlier posts of yours, you were wanting to run a top mount tank. So at that point you have nowhere to put the stock airbox.
So I was under the premise you were going to run a top mount tank.
That is why I suggested the pod filter for you.

[Just-Tri-It]

That's right I was running a zinger tank because the previous owner had a lower tank of some kind on it. He didn't have a pump. So I was going back as much stock as possible after putting a pump on it. I took the 38 pwk off temp. and put the 38 pe on it and the boot slipped on fairly easy. I got an extra boot so I'm going to mold it with the pwk off the bike for ease of handling.
But on the tank I just didn't like the zinger tank set up that much. That's why I was trying to go back stock as much as I could without sacrificing performance. Trail and error I guess plus these suggestions from the board.
Thanks

[Mosh]

^^^ Ohh ok I see.

Understandable on the tank deal.
We have a guy here local that may start making some aluminum top mount tanks like the Klemm, but it is still in planning stages right now.
I will let people know if it happens.

boiling those boots in water with oil soap works good for strecthing them.

[Just-Tri-It]

Look, I want to pursue this thought on the air intake volume because it got me to thinking about the air duct and the amount of air that can be delivered through it to the 38 carb to the cylinder. Is the stock tubing incapable of delivering enough air with a lid with the additional hole in it to get maximum performance from the 38. Or is the tubing to small no matter how many holes are in the lid to bring the 38 and the engine to its peak performance. The tubing is pretty large except at the elbow of the boot. If the stock tubing can't deliver the necessary volume of air needed then I am wasting mine time putting it back on the bike. Just sort of thinking out loud here. Thanks for any insight.

[tri-Z ripper]

I don't run an airbox lid. Maybe in the winter when the air is more dense. But running open filter is foolish unless you only ride sand! Just my 2c I ride through water and mud not by choice when I ride.