
(*´Д`) I remember DYNOJET from way back~
I searched the company website bit by bit and… there it was~
But! I couldn’t get it directly from the company website… (dealer system issue?)
So I ordered it from eBay instead.
International shopping is convenient these days, though the weak yen is painful (*´ω`*)

What I ordered was the E2110
Let me note down what I researched.
Are there 3 types of Dynojet for the Zephyr 550? What’s the difference?
If I buy the wrong one, won’t it work?
That’s the question that came up.*Dynojet Zephyr 550 page
So I asked about it (*´ω`*)
“The C represents Canadian variant ZR550 Zephyr, The E represents European variant ZR550 Zephyr, and SKU# 2110 is for the USA variant ZR550 Zephyr.”
C represents the Canadian version of the ZR550 Zephyr,
E represents the European version of the ZR550 Zephyr,
and SKU# 2110 represents the USA version of the ZR550 Zephyr.
I see! It seems to be modified depending on the region of use.
Since the carburetor bore diameter is the same, I decided to check the jets inside.
*Bold text means mostly common.
USA California & Canada & UK
Needle N67JNeedle jet 16017-1292Jet holder 13091-1406SJ#35 MJ105 (OP102/108/110/112/115)Spring 92081-1761
Europe
Needle N2NVNeedle jet 16017-1292Jet holder 13091-1938SJ#35 MJ100 (OP102/108/110)Spring 92081-1912
Well, they’re different but I think it’ll work out somehow.

When I opened it, it looked like this.
・MJ in sizes 96 and 100, four of each
・3φ drill
・Unnumbered jet needle
・Washers x 8 pieces
・E-clip
・Useless instruction manual

Translation is easy with GOOGLE Lens
The more I read it? Huh?
According to the manual, drill with DD29 drill! (Included is DD31 drill)
Attach the clip to the second row from the top! (The diagram shows the third row)
Hmm… This is getting weird… DYNOJET
I can’t proceed and need to research.
The slide valve hole diameter will be enlarged.


That said
SKU# 2110 is for the USA variant ZR550 Zephyrwas the only one I could find
and I used it as a reference for comparison.

It looks like a thinner needle visually (not measured)
I didn’t bother checking.

With the CVK vacuum carb, the clip position can be adjusted, which is nice.
However, the needle retention becomes loose, so you need to insert washers.

Put two on top! That’s unreasonable…
Solder and iron are the perfect match♪
I combined the two into one.
And thinking about it later“O-ring”would be better.
It sits firmly and you can apply tension too, isn’t that the best?
If you’re going to set it up, you should keep it as clean as possible.

The slide valve hole diameter was 2.5φ.
I’ll enlarge it with the included drill.


Is the included drill DD31?
The actual measurement is 2.9, which makes it a 3φ drill.

While I had the carb off, I removed the carb heater.
Basically, a simple configuration is a must (*´ω`*)

One was directly attached, so I removed that too and fixed it with the same screw~

There’s an atmospheric sensor on the air cleaner box, so I removed that too
It was M16 or something…
I happened to have a blind plug lying around, so I used it to cap it.

While I was at it, I replaced the throttle and clutch cables
I think this made the biggest difference.
You should replace cables within 10 years.
New ones have performance beyond just lubrication (*´ω`*)

The Zephyr 550 winding diameter is 32φ
When disassembling, just applying a caliper for a few moments gives you lots of information.
Repeating this for just a few minutes accumulates a considerable amount of knowledge.

The Zephyr has a really weird frame.
Well, I’ve completed the installation for now.
I haven’t test ridden it yet, but I think the response should be better.
Just revving it up feels really smooth, so it’s definitely going to feel good.
