Conversion from 125 cc to 175 cc on a 73 Six-Days

[john durrill]

Hey Folks,
 We have just about got the project done. We got some pictures scanned of the motor parts we had to modify and should have some of the engine assembled tonight.
Can post them some where if any one would like. Right now they are on the Vinduro group web page.
We use some trick's that the Holland Importer for Monarch did in the 70's to come up with a Sachs/ KTM 175 GS / 5
The folks from Holland were able to win some gold with it in the Six-days.
JOhn & Peter

 

[john durrill]

Have some new pictures of the motor built.  we uploaded them to the Vinduro Photo section under Woolfs Old bikes.
Here is the web address if you would like a look at the project.
http://groups.yahoo.com/group/vinduro/


 the motor is ready to go back in the frame, so we should have it running soon.
John



Edited by - john durrill on 07/01/2002  11:16:54 PM

Edited by - john durrill on 07/01/2002  11:17:53 PM

[OUCWBOY]

John,
Looked at the photos of the conversion. Motor looks great. Was wondering why you went with a KTM cylinder instead of using a Sachs 175? I would like to know more detail of the process.
Thanks
Donny

[Dwight Rudder]

Donny, He went with a KTM because the KTM stroke is same as a Sachs 125. The Sachs 175 which didn't even exist until 1974 has a much longer stroke. KTM 175 pistons are more plentiful ( as rare as they are) than 175 Sachs pistons.
Cher'o,
Dwight

7 time ISDT / E medalist
7 time National Enduro Class Champion.

[OUCWBOY]

Dwight,
Thanks for the info. I now see the light! What is the bore x stroke on a 175 Sachs? Thanks!
Donny

[Dwight Rudder]

60 X 61 mm
GS175/6a Hercules only sold in the USA in 1975.
This engine was only build from 1974-75.
Dwight

7 time ISDT / E medalist
7 time National Enduro Class Champion.

[john durrill]

Sorry i havent checked back and answered Donnys questions sooner. Thanks Dwight .
Got the motor running last night . 3 kicks and it fired right off. still some small things to tend to. it idled and would take throttle so the Lectron must be close.
Anyone on here use Lectrons? the instruction say to use a pair of pliers to adjust the needle for idle mixture...... the thought of touching a needle with pliers sends a shiver up my spine!!! chuckle chuckle.
Any suggestion on what would be a better way to do this?
John