Modern Vespa

I stumbled onto this awhile back and wanted to share. The article on the web says it was last updated April 6 2020 but I thought I had seen it before that.

I collect reference books, yeah I know I am a geek. I personally think Kevin Cameron is a genius. I can remember reading an article he wrote about how a nut and bolt is a spring tension fastener when I was a kid ( I am 63 now so it may have been close to 50 years ago ) and was fascinated with it. I am pretty sure Kevin is to blame for me geeking out on stuff like that, although the tendency may have always been there it was Kevin's well thought out analysis in writing that really shined the light on it.

https://www.cycleworld.com/story/bikes/kevin-cameron-explains-how-to-tune-carburetors/

After reading this and studying it for a bit is when I became an even bigger fan of fuel injection.

From the article..."For a street machine a slightly rich indication is good, together with steady running on top-end. Leave the bone-white plugs and the last few top-gear rpm to the racers, who are going to change their jets every time the sun goes behind a cloud anyway (modern digital engine management systems do this for you automatically). Make your jet changes and repeat your tests with fresh sets of plugs each time, always using the same heat range. Such work consumes a lot of plugs, so you may want to clean them for reuse as suggested to me years ago by "the Champion man," Bobby Strahlman: oven cleaner, followed by a water rinse."

If you have an older carbureted machine this article is the gospel. I have it saved as a reference and even if you don't have to do it very interesting for me to learn how it is done.

Again from the article..."If this procedure seems time-consuming and laborious, you should consider that factory carburetion engineers of the past did exactly the same tests on every new design, at some point in its development. When you make changes in your machine, or if you have special carburetion requirements, you can get what you want by using such methods."

Thanks for posting!

Thanks for the post. This may be just the information that I need to get my Honda CM200T running right. I have a problem with carbon deposits now using the original carb with an original jet. I should be able to figure out now how much needle adjustment or spark plug changes I should make. I am fairly close now and have considered leaving the carb set up as is and just carrying a set of new plugs with me to switch out when the ones in engine carbon up.

Glad it was helpful.

I think every article Kevin Cameron ever wrote was really good and I think it is worth searching his articles anytime you need information about something, if Kevin wrote about a subject he breaks it down and explains it pretty well.

Hi

Maybe this tutorial from SIP works for you

Regards