Page 1 of 1
Original main jet?
Posted: Thu Mar 11, 2010 3:54 pm
by mk2davis
I'm trying to find out what the "correct" main jet size is? I know this is a loaded question, and I am taking a risk asking it, so let me give you a little background.
I bought my Benly after it was in storage at darn near sea level for 30 years. The main jet is 100. I also ordered a carb rebuilt kit, and the included main jet was a 92. I have no reason the think I'm too rich, and frankly I'd rather error on that side, so I kept the 100 in. I'm at 600-800 feet.
Ideas?
Posted: Thu Mar 11, 2010 5:35 pm
by BenlyBoy
By the parts book the standard main jet for a CA95 is #92. Standard main jet for the C95 is a #100. I have a pair of original C95 Benly's and the main jets are indeed #100.
While the above are the standard sizes, the parts book does list jet sizes #85 to #105 for the CA95, and jet sizes #90 to #110 for the C95. For tuning purposes perhaps?
Posted: Fri Mar 12, 2010 8:28 am
by mk2davis
I thought the CA was the hotter motor; I'm surprised it uses the small jet. I think I'm going to stay with the 100, especially since I'm using a Uni airfilter. A sin, I know.
Posted: Mon Mar 15, 2010 11:06 pm
by Sam Green
The carbs did change over the years and the listing for both models in 1960 was 95 mains in both. I do know for a fact that my 65 C95 had 100.
It's not ultra critical for normal riding unless you live at altitude or are racing.
I have a full jetting chart for C92 C95 CB92 CB92R and CA95 as at June 1960.
Sam.

Posted: Tue Mar 16, 2010 6:10 am
by BenlyBoy
I have read that the CA95 carbs had a power jet and the C95 carbs did not. Have never seen a CA95 carb, and the parts book does not list any thing like a "power jet". How does the power jet work? Would it affect the main jet size compared to the non-power-jetted C95 carb?

Posted: Tue Mar 16, 2010 9:52 am
by Sam Green
The CB92 and CA95 both make power at 1000rpm higher than their C counterparts. The power and power air jets are to aid breathing at these extra revs.
These extra jets should not make any difference to the size of main jets.
Sam.
