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Timing map

4K views 5 replies 3 participants last post by  RecoilRob 
#1 ·
Has anyone mapped or knows the timing of our stock gen 1s in each gear. I hear about the 2nd and 3rd gear making is slightly retarted from the factory, i just want to know how much and where this reduced timing lies on an RPM scale.
I would assume the little TPS has something to do with this as well

More on why I'm asking this but i want to change which map the bike is using on the fly to have different riding modes.
 
#4 ·
I can show you ignition maps for the 1K...but not the Pointy 650. The timing really isn't all that much different in the various gear maps, and when it is...it's only where they actually test them for emissions (both noise and exhaust). Any timing variables beyond where they must pass a test is there for very good reasons and will likely be very close to ideal.

Check out the 1K maps below and you'll see they are very similar except at light throttle and low revs. The totally stock engine seemed to like the blanket 4 degree advance from a split-key, but the top-end was not improved and might actually have been hurt by it.

With increased compression and altered cam timing the engine most definitely didn't want more timing and might actually run better with it retarded a bit, but I'm pretty sure this would hurt the cruising mileage so I've left it alone...for now.

Edit: Wanted to add that you could check your timing curves by marking the flywheel rotor so you can watch it with a strobe timing light through the timing hole. Make a clear plastic plug so oil doesn't fly out and run it on the dyno and plot the curves. That would be the best way to figure out what you have so you can then figure out where you want it to go.
 

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#5 ·
Thank you very much!
What i was hoping to see was a slight drip in timing on the top end in a lower gear. I have advanced my timing 4 degrees already, made cruising mpg and torque jump up a good bit but i lost a lot of high rpm pull. I was planning to set up a switch on the handle bar or better yet on the carb itself activated my throttle position to trick the computer into thinking its in say 2nd gear reducing the top end timing giving me back that lost power.
ill be able to have my cake and eat it too by the looks of it
 
#6 ·
I see....but from what I've been able to determine, I don't think the high-rpm timing is very different on the various gears maps....and not enough to bother with. The better way to 'have your cake and eat it too'...is to bump up the compression and increase the effective compression by altering the cam timing...that way the stock timing curves work well and no need for the 4 degree advance key.

As it is, the key is kind of a band-aid for the bottom and midrange and on a hard pull the engines don't really seem to need more than stock timing up at high rpm...particularly if you're going to be running it hard. There have been a few 650's that scored the crap out of their cylinder walls which I think was from detonation...and they were running 87 octane fuel. With the timing advanced I'd not run 87 were I you.:)
 
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