Author Topic: Plastic main jets  (Read 765 times)

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Offline perrito

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Plastic main jets
« on: April 20, 2017, 06:37:10 AM »
Hey guys, I have a set of 127.5 plastic main jets that came in a set of carbs I bought years ago- I saw something about them a few years back but can't find any info now- anyone know anything about these? Why they were made?
Thanks.

Offline PeWe

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Re: Plastic main jets
« Reply #1 on: April 20, 2017, 08:21:57 AM »
Nylon jets were available here in the middle of the 80's. White ones. They had a name I do not recall.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline ekpent

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Re: Plastic main jets
« Reply #2 on: April 20, 2017, 08:42:53 AM »
 I had some nylon jets also 'back in the day'. Our local Honda dealership had a multi compartment case with all different sizes. They were quite cheap to buy which made tuning more reasonable and they could be drilled very easily.Do not recall any name brand either. They are probably still kicking around the shop somewhere.

Offline PeWe

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Re: Plastic main jets
« Reply #3 on: April 20, 2017, 10:58:37 AM »
Pro-Jet from  PRECISION SYSTEMS INC. They had sets with several sizes. I'm not sure if this was the name I was looking for.
I found a set in Sweden. An old shop that might have stock from the 70's-80's
http://www.roffesshop.se/index.php?route=product/product&manufacturer_id=156&product_id=268

I bought my new 16" Henry Abe rear wheel here.

CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline ekpent

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Re: Plastic main jets
« Reply #4 on: April 20, 2017, 02:33:25 PM »
 Just out of curiosity PeWe can you translate that kit for me into USD dollars. Wondering if they are still cheap.

Offline BomberMann650

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Re: Plastic main jets
« Reply #5 on: April 20, 2017, 04:08:43 PM »
I'm assuming these are for trail and error tuning purposes (as mentioned) but not ideal for regular use?  Right?  Because ethanol sucks

Offline PeWe

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Re: Plastic main jets
« Reply #6 on: April 21, 2017, 08:42:35 AM »
310 SEK (kr) = 34.60 USD  (Currency is good for you, bad for us in Sweden when order from USA)

Now around 9 SEK/ 1 USD. Not long ago 7 SEK/ 1 USD

VAT here is 25%. They should remove 20% if shipping to USA :)
Text can be translated with google translate  https://translate.google.com/?hl=sv
Like this:
Small plastic box with KEHIN nozzles in nylon. Round model with track groove, which fits most HONDA. 4 nozzles of each size: 105. 110. 115. 120. 125. 130 total 24 pcs, included. (See also loose nylon nozzles KS).
« Last Edit: April 21, 2017, 08:47:00 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline seanbarney41

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Re: Plastic main jets
« Reply #7 on: April 21, 2017, 05:20:16 PM »
I'm assuming these are for trail and error tuning purposes (as mentioned) but not ideal for regular use?  Right?  Because ethanol sucks
surprisingly, the ones I have seen have held up fine.  Keep in mind, that by the mid '80's many carburetor assemblies contained comparatively large amounts of plastic right from the fatory.
If it works good, it looks good...