TBR7 Carb Upgrade

[Megadan]

Originally Posted by Nospark

Megadan, Thank you for the specifics on the carbs. I'm curious why you didn't mention a change to the pilot jet as well. Is there not a concern going to 115 main will be ahead of the stock pilot jet during transition? My thinking now is stick with the PZ30 until the mods get to a point someday where I want to look at other intakes. I can envision performance exhaust,air box delete & sprocket size changes but doubt I'd go further with mods.
I tried to locate NZbrakelathes as well but, no success.

I didn't mention it simply because I am unfamiliar with what the stock pilot is on the other bikes. The Hawk pilot jet from the factory is actually more than sufficient, and often only the main jet, needle, and idle mixture need changing/adjusting.

On most 100% stock bikes, assuming the pilot jet is sufficient from the factory, a 105 -107.5 main jet is usually more than enough, maybe a 110 if you are right at sea level.

[Nospark]

Magadan, jetsrus didn't show a listing for a PZ30 carb, or carb rebuild kit. PZ27 is all I can find on the site. What am I missing?

[kyle]

Commented on your other thread.. but you have options and others out there that have documented known good jetting per elevation and modifications and type of carb: https://tbr7.com/upgrades/fuel-system/

[Thumper]

I am finding AliExpress to be a remarkably good source for inexpensive and useful jetting kits. And they are showing up within 3 weeks. I got a couple of sets of the upper half of the two piece jets that are in my Bashan Storm ("youALL" PZ30) and my son's new TBR7 PZ30. PERFECT fit! And the only source I know of for these the upper half (jet nut) of these odd two piece pilots. The original PZ30 carb works as well as any clone, and you have to jet anyway. Buy a new one if you think it will help. Then buy jets too

And now I just ordered another main jet set with close differences (110, 112, 115, 118, 120, 122, 125, 128, 130, 132) for $5.59 plus $2,49 shipping! The next set down goes from #88 to #108. We pulled an #88 from my son's brand new TBR7 (carb still dry!), and replaced it with a #108 for starters, and replaced his #36 pilot jet with a #38. We will undoubtedly make more adjustments. For now, we've made no airbox or exhaust mods, so these initial changes should be good. And yes, we shimmed the needle ~1.5mm while we had the carb out. The garage is still freezing cold, and we need to get the rest of the bike together

Here is a picture of the comparison of original and the replacement pilot jet. The replacement is the shorter one. But it fits perfectly. The end is immersed in the gas in the bowl, so it doesn't matter.


Here are dimensions:



The lower half of the pilot can be seen in the recess:

[CheapThrills]

I just had the longest run on my New Nibbi PE30 (air pod and aftermarket exhaust) and the bike ran GREAT. Now to get here I had to play with the jets, but the engine feels like it actually "pulls" in higher gears(Oh running, 17t/42t, and weight about 200+ with gear).

[Nospark]

Thumper, Can you provide a link to the jets? I've been slowly getting the bike together and am ready to pull the carb and rejet.

[Thumper]

Originally Posted by Nospark

Thumper, Can you provide a link to the jets? I've been slowly getting the bike together and am ready to pull the carb and rejet.

sent you a pm

[Thumper]

I just got another awesome link to jets from a vendor on AliExpress.
I actually ordered a set like this (different selection). This is a lower price, and broader selection!
The point is, there is no problem getting jets for our bikes. Jets are cheap and available
MYTH BUSTED!

[Nospark]

Thumper, Thx for sharing. My jets showed up yesterday. Waiting for the carb I bought to show up hopefully today. Took the new stock carb off yesterday.
Here is a link to the carb I bought. Nothing special over the one that came on the bike other than no need to slot float bowl screws.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
If the jets I bought don't fit the new carb, I'll perform surgery and disassemble the one that came with the bike. They should fit that one

[Nospark]

Cheap Thrills it's great to hear the 17/42 combination works great for you. I'm same weight so hopefully I'll achieve similar results. I'll likely do the air box cut-a-way mod but, not sure about exhaust yet. I want to ride it for a bit before I start getting into more after market upgrades beyond where I'm at. Spring can;t come too soon here in Milwaukee

I have main jets 100, 105, 108, 110, 115, 120, 125, 130, 135, 140. I'm thinking of starting at 108 with 38 pilot and shimmed as Thumper mentioned. Milwaukee area being 600ft elevation. This should get me running.

[Nospark]

Took apart the New PZ30 clone this morning to rejet. It came with a 105 main & 40 pilot.
Reading all the help and input here to understand a good starting point. I chose a 108 main & 38 pilot. Set idle mixture 1.5 turns out.
Again I'm at 600ft elevation here in Milwaukee and stock air box & exhaust for now.
Feedback on if my setup seems like a good starting point or not is welcome.
BTW, I have not performed surgery on the carb that came with the bike yet to see what's in that one.

[Nospark]

Oh, and I positioned the needle washer on the 4th notch down from the top out of 5.