Penton Owners Group

General Discussion => Penton Talk => Topic started by: skiracer on August 25, 2017, 04:12:44 PM

Title: Mikuni jetting on a 6 Day
Post by: skiracer on August 25, 2017, 04:12:44 PM
Looking for a jetting starting point with a 32mm

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer
Title: Mikuni jetting on a 6 Day
Post by: Larry Perkins on August 26, 2017, 06:03:37 AM
Can not help on that one but curious if the motor has any port work done on it because a 32mm is very big for a piston port Sachs 125 motor.  The original porting had no bridges to be able to add much size and no booster ports so I never ran one bigger than 30mm and that one had been dremeled to the point that it went through rings pretty quickly.  That is a lot of flow.  also post later how it works out if you do not mind.  Thanks!

Larry P
Title: Mikuni jetting on a 6 Day
Post by: skiracer on August 26, 2017, 07:18:03 PM
Actually a fellow member has the bike, and I have the carb.  I appreciate your input, hope all is well.....

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer
Title: Mikuni jetting on a 6 Day
Post by: Dale Fisher on August 26, 2017, 08:25:47 PM
I run a 32mm on the Cheney Sachs and it scoots much faster than my ability.  The recently completed Berkshire came with a 32mm spigot mount that slips right on like a Bing but it hasn't been completely sorted (leaky gas tank and sticky gas metering needle).

Back to the Cheney...  I thought that I had scanned the clipping but it looks like the Carb, adapter mount, and slide were all part of a hop up kit.  The slide has been altered with the angle portion larger the what the catalog/marking indicate.

(http://i957.photobucket.com/albums/ae59/CheneySachs/Cheney%20Pics%20026_zpsojzziqsq.jpg)

(http://i957.photobucket.com/albums/ae59/CheneySachs/DSC_0372-crop_zpskyxkpgrh.jpg)

Dale Fisher
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Title: Mikuni jetting on a 6 Day
Post by: HeathRobertson on August 26, 2017, 10:18:58 PM
What size Jet Dale?  Or ballpark even, just something to start with?
Title: Mikuni jetting on a 6 Day
Post by: Dale Fisher on August 27, 2017, 07:33:41 AM
I pulled this up using the search function.  The jetting for the Cheney won't help too much since the needle (unavailable) and slide (modified) are unique.

Originally Ernie Page's work?

(http://i957.photobucket.com/albums/ae59/CheneySachs/jetting5-13-08_zps9ntlnzz6.jpg)

Dale Fisher
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Title: Mikuni jetting on a 6 Day
Post by: KJDonovan on August 27, 2017, 08:13:57 AM
James / Heath,

I had these written down as a jumping off point.

169N8-Needle Jet
5F21 Needle (Clip on 2nd slot from top)
40 - Pilot Jet
155 - Main
2.5 Slide

May be a little rich, but better rich than lean.

Thanks,

Kevin
Title: Mikuni jetting on a 6 Day
Post by: Mickey Sergeant on August 27, 2017, 04:45:17 PM
I run a 32mm mikuni on my 125.  Ported motor.
sea level 175 main
2500ft 170
4300ft 160
don't remember pilot or needle. what ever it came with is what is in there
I have been running this for 3years now

Mickey
Title: Mikuni jetting on a 6 Day
Post by: skiracer on August 27, 2017, 06:33:09 PM
Great photo!  Thanks for the input.

Quotequote:Originally posted by Dale Fisher

I run a 32mm on the Cheney Sachs and it scoots much faster than my ability.  The recently completed Berkshire came with a 32mm spigot mount that slips right on like a Bing but it hasn't been completely sorted (leaky gas tank and sticky gas metering needle).

Back to the Cheney...  I thought that I had scanned the clipping but it looks like the Carb, adapter mount, and slide were all part of a hop up kit.  The slide has been altered with the angle portion larger the what the catalog/marking indicate.

(http://i957.photobucket.com/albums/ae59/CheneySachs/Cheney%20Pics%20026_zpsojzziqsq.jpg)

(http://i957.photobucket.com/albums/ae59/CheneySachs/DSC_0372-crop_zpskyxkpgrh.jpg)

Dale Fisher
Penton Owners Group - President/Memberships
POG Merchandise
Mudlark Registry
Facebook - Penton Owners Group - Administrator
Facebook - Cheney Racing Group - Administrator

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer
Title: Mikuni jetting on a 6 Day
Post by: skiracer on August 27, 2017, 06:34:00 PM
Thanks everyone for the help with your input. It is well appreciated!

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer
Title: Mikuni jetting on a 6 Day
Post by: HeathRobertson on August 27, 2017, 10:04:50 PM
Yes, thank you all for the input!  Much appreciated
Title: Mikuni jetting on a 6 Day
Post by: JP Morgen on September 03, 2017, 01:07:45 AM
6F5 needle is key
Title: Mikuni jetting on a 6 Day
Post by: skiracer on September 03, 2017, 05:42:14 PM
And what needle jet goes along with that?????

Quotequote:Originally posted by JP Morgen

6F5 needle is key

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer