Critique my timing table

Tuning concepts, methods, tips etc.

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aw113sgte
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Critique my timing table

Post by aw113sgte »

My timing table is what is generated by http://www.useasydocs.com/theory/spktable.htm
I do not have access to a load bearing dyno so I will be doing what I can tuning on the road.
What I am seeing from 1000cc 4 cylinder bikes is total timing about 40 degrees. Since I will be boosting up to 10psi, the common suggestion of 1degree/1psi so that would put my total timing around 30deg, however the calculator spits out 18.6. Thoughts?

My table:
map2d.jpg
My motorcycle specs for table entry:
ign calc.jpg
Table of an R1 (same bore/stroke as my WR250X, similar head design, different cams etc).
09R1ignGear6.jpg
elutionsdesign
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Re: Critique my timing table

Post by elutionsdesign »

I'm certainly more in agreement with the MS timing table, a mulitvalve chamber with swirl/tumble (stumble) at that static compression ratio should never need much timing as it is quite a bit more efficient than a two valve pushrod motor. I would start at something in the mid 20's for total timing but I would drop it less than 1 degree per psi boost. Then I would find a constant load dyno.
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grom_e30
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Re: Critique my timing table

Post by grom_e30 »

from looking about my self motorbikes do seem to run a hell of a lot of ignition advance.
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dontz125
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Re: Critique my timing table

Post by dontz125 »

This is the curve of an '87 FZR1000; 75 x 56mm, 11.2:1 compression. No TPS and no EXUP, and most of the FZRs were considered to be detuned by about 5* vs what you could run on typical (87) pump gas. With a TPS, you should have no issues adding a LOT of advance at part-throttle operation. Obviously, pulling advance as you boost ...
FZR1000T.jpg
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aw113sgte
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Re: Critique my timing table

Post by aw113sgte »

I've updated the timing table and here is what I am running now. Bike runs well, unfortunately without access to a load dyno I am left guessing. I also can't detect pinging/knocking....single cylinder motorcycle.
timing2.jpg
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