advanced timing

vette76 · Post by **vette76** » Sun Feb 20, 2005 10:33 pm

does a spree have a key that holds the flywheel to the shaft? i found a special key for a pocket bike that advances the timing. is this a good idea?

check it out. here it is.

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... eName=WDVW

vette76 · Post by **vette76** » Sun Feb 20, 2005 10:55 pm

what is the purpose of the reed valve, and how does it work?

Post by **noiseguy** » Mon Feb 21, 2005 9:08 am

1) You could probably machine something to advance the timing on the Spree, but you would need to watch/listen for predetonation. You could blow a rod if it's not set up right. A dyno would be a good way to tune this.

2) Reed valves open when outside pressure exceeds inside pressure. This lets fuel in at the right time, just like intake valves on 4-strokes. Go to the MacDizzy site and look for info there.

vette76 · Post by **vette76** » Mon Feb 21, 2005 12:49 pm

noiseguy wrote:1) You could probably machine something to advance the timing on the Spree, but you would need to watch/listen for predetonation. You could blow a rod if it's not set up right. A dyno would be a good way to tune this.

2) Reed valves open when outside pressure exceeds inside pressure. This lets fuel in at the right time, just like intake valves on 4-strokes. Go to the MacDizzy site and look for info there.

does a spree have a key like this and would it fit?

Post by **noiseguy** » Mon Feb 21, 2005 1:32 pm

Not likely.

Tippmann98 · Post by **Tippmann98** » Sun Feb 27, 2005 12:21 am

That is a good idea for a mod. I may look into this