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Discussion Starter · #1 · (Edited)
I posted them last summer but my photo host must have dropped the pics cuz the graphs are no longer visible. The first runs, have the choppy lines (which I traced with highlighter) because of a problem with the dyno set to read every 360*. The tuner then put both leads on one plug wire and had it read every 720* and the traces were fine. The rest of my build is pretty well covered in my signature line.

Constructive comments appreciated. I think there is more power in there...and that I lost some of it running too much advance on the ignition. DTT recommends no more than 30* advance at 5000rpm and up...and at the time of this tuning, I was running 35*. I have since rectified that, and I can't wait to get it back on a dyno this spring.

FYI: The first graph is a best run WITHOUT the air cleaner on. Second graph has the air cleaner on and shows the AFR. Third graph is the before and after comparisons. The only real change made to between runs was to richen up the top end with a bump of the main jet from 205-220.
 

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Seahag,
just read this post, i'm no expert, just your build is close to my own build.
i retarded the crane hi-4tc -5 degree i think i use the 6 or 7 advance curve. i've got wisco 10:5.1 pistons. i have stock heads ported by a friend here in australia 1.90 intake 1.625 exhast. 55g cams stock head pipe cycle shack slip-ons woods 43.5 se manifold. i found the se manifold restricts flow a bit, i got better flow useing S&S manifold. but still running the SE manifold. i went from riding and racing this FXD 01 to just racing it as i had a bad accident with a cadge this time last year and broke left leg in 4 places below knee and above ankle, they put a rod inside the bone. i'm ok now, just wanted to explain as i made some changes to the tune that are fine for just racing but not sure what it would be like on the street, but i ride it back to the pits and up to the line and onto the trailer seems fine. i had about 100TQ & 97HP 3.37 gears with chain rear makes it 3.41, i use stock HD cast wheel and 150 tire, but am getting 17 light weight wheel to use shinko or micky thompson soon. any way i removed the air cleaner and removed the baffles from the slip ons and at the track it showed increase in trap speeds and the ET's dropped so after 6 months racing desided to check it on dyno again as had not check with air cleaner removed and baffles removed, i also went up two thouh in main jet ( wood uses thou increasements in jets ) got 105hp 105TQ in 4th gear SAE on DJ 200 its just the dyno i always use. the pipes and aircleaner seem to make big gains or losses. best time at the track 11.34 1.64 best 60' speed is 116mph.
i now have bike ready to lift heads to check out motor as has 50,000 on it.
 

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Discussion Starter · #3 ·
Thanks for verifying my new ignition settings. At the time of my dyno tune, I was running -1 initial with a 4 advance...which the tuner upped to 6...so I was extremely advanced for 10.5 compression.

My early thinking was to run a flat advance curve; but it wasn't working out in the heat; so I switched strategies to a lot of retard initially and a more agressive advance.

After looking at the crane software to compare curves, I settled on -5 initial and a 6 advance curve. No more pings, and better starts. I'm hoping for a little more HP on the dyno too. I figure if the ignition was firing too soon, the igniting charge would be fighting the upstroke of the piston on the compression cycle and robbing some of that upper end horsepower...Does that sound like a valid theory?
 

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I'm sure you would have picked up a few horses retarding timing. i ran mine @ 0 adance and #5 curve, then moved it to -5 and a more agressive advance and picked up HP & TQ i've just left it there.
i have some S&S 625g cams and after checking motor out will put some new rings in and set the heads for the higher lift, also will use an S&S G manifold and will inter change between the S&S D & the wood 43.5. i'll probably go slower at the drags till i get usedto the new set up, when i get used to it, i'll go to next stage, have some spare heads afriend will weld up port floors and has fitted 2" intake will get the intake out to 1.8 and am waiting for som 30 degree top higher comp pistons, will machine the chamber to suit and run it at a tight swish. just trying to see how quick i can get the 95" to go. would like to latter go with some of those nikasil 4 1/4" bore barrels with 30 degree pistons but want to see how quick i can get the 95"
 

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I'm running 1 initial and 6 advance and doing fine except at the very low rpms - like when I first let out the clutch and give no gas. When the rpms drop below 1000 - I get slight ping. So... I bought the cable for my DTT and will play around with the initial setting down low.

In setting the ignition on the dyno, it was interesting to see the improvements up to 6 - and then the drop at 7.

Seahag, I see you have the Hypercharger and stinger, so I think you're breathing better than mine is. I'm thinking of upgrading to something - but haven't decided what.

Given we have similar builds, I'll be watching to see how your tweaking works out and I'll post my results too.
 

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when i work with advance curves carburated bike first fint the curve that gives best torque numbers then find the curve that give best advance ussually less agressive that the torque curve then using your sofware above the max torque numbers plug in the upper half of the hp curve by blending the two curves tegether torque and horspower can be maximized
 
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