mallory timer, advance curve
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eve'n folks, i sense that the flatheads advance curve is way to quick robbing my get up and go, all is well at full advance. i'm running a mallory mechanical advance timer. i've been searching the web but am coming with nothing per initial timing and full advance... what would be the total degrees from retard to full advance? what rpms do the ul's like for full advance. my starting point will be how many degrees of total timing and then the rate at which it advances and then full advance setting. the mallory has a selection of advance springs and adjustable total timing. from reading the ul manual seems somewhere around 32 degrees is close for full advance......with the original timer did the rider have to retard the motor under certain conditions such as pulling a long steep hill or idling along in city traffic? do these old ul's detonate like an ohv when they're not happy? after 3600 miles i have yet to hear any detonation, but can feel a mild roughness around 55/60 mph when advanced a tad too much. thanks for any help....i may have not expressed my question too clearly but hopefully someone will give us all a lesson in flathead timing and modern mech advancers!..........mark andrews
Re: mallory timer, advance curve
mark59
I'm not NEARLY the expert some on here are. My 80ci runs well at about 29 degrees full advance. I'm not famialiar with the Mallory system but have seen some with several different springs. How does the Mallory advance unit limit the total advance? I modified the sporster type advance to limit the total advance. Mine kick starts well at about 17 degrees initial advance and seems to have as much power as I would expect.
F
I'm not NEARLY the expert some on here are. My 80ci runs well at about 29 degrees full advance. I'm not famialiar with the Mallory system but have seen some with several different springs. How does the Mallory advance unit limit the total advance? I modified the sporster type advance to limit the total advance. Mine kick starts well at about 17 degrees initial advance and seems to have as much power as I would expect.
F
Re: mallory timer, advance curve
32 seems to be what the manuals call for, but I've had individual motors vary greatly. My 88 stroker does ping on 32, I'm in the process of dialing it back to the happy medium where it pulls well with no pinging.
For normal 80's I'd say that "F's" numbers are about right. I've played with the manual advance for years, on the flathead it seems to just shift the power band up and down the rpm range. More retarded for low end grunt, advance to lose some low end, gain the power in high end. ( I realize that "high end" is relative when speaking of flatheads !)
I made an attempt to create my own electronic advance unit awhile back, and had decided that a linear gradual increase of advance from idle 7-800 to about 2500 would be a good compromise.
As a final note, I got a hold of a 45 auto unit last year and tried that. It had very weak springs, and advance kicked in very quickly. I'd swear it was fully advanced by 1000 rpm's. basically just used to avoid kick back damaging the electric start.
Unfortunately, I didn't have a chance to measure the full range of advance of the unit before I got rid of it.
I think the old timers only used to retard the motor for starting and pulling stumps on the back 40.
DD
For normal 80's I'd say that "F's" numbers are about right. I've played with the manual advance for years, on the flathead it seems to just shift the power band up and down the rpm range. More retarded for low end grunt, advance to lose some low end, gain the power in high end. ( I realize that "high end" is relative when speaking of flatheads !)
I made an attempt to create my own electronic advance unit awhile back, and had decided that a linear gradual increase of advance from idle 7-800 to about 2500 would be a good compromise.
As a final note, I got a hold of a 45 auto unit last year and tried that. It had very weak springs, and advance kicked in very quickly. I'd swear it was fully advanced by 1000 rpm's. basically just used to avoid kick back damaging the electric start.
Unfortunately, I didn't have a chance to measure the full range of advance of the unit before I got rid of it.
I think the old timers only used to retard the motor for starting and pulling stumps on the back 40.
DD
Re: mallory timer, advance curve
fhsmith1, here's a link to a pdf on mallory's timer with instructions showing advance adjustments
http://static.summitracing.com/global/images/instructions/maa-29014%282%291.pdf
frankenstein, my timer is set up to retard to kick it over and when she fires up it's advanced or just about to, much like the electric start 45 timer did. fhsmith1, so you're running about 12 degrees from 17 to 29, thanks for a baseline to work with. i was taught to run 50 miles on any one given change be it carb or ign ( assuming that the change is acceptable to run the motor safely ) it does pay off but it takes time, i remember finally getting the ign right on my old shovel stroker, boy did that feel good when she pulled strong all across the rpm range. i'm having a grand time riding the flathead and i have no interest in riding the shovel or twincam.......dam i always wondered what a real harley (f head or flathead) would feel like.........it's addicting!...............thanks mark
http://static.summitracing.com/global/images/instructions/maa-29014%282%291.pdf
frankenstein, my timer is set up to retard to kick it over and when she fires up it's advanced or just about to, much like the electric start 45 timer did. fhsmith1, so you're running about 12 degrees from 17 to 29, thanks for a baseline to work with. i was taught to run 50 miles on any one given change be it carb or ign ( assuming that the change is acceptable to run the motor safely ) it does pay off but it takes time, i remember finally getting the ign right on my old shovel stroker, boy did that feel good when she pulled strong all across the rpm range. i'm having a grand time riding the flathead and i have no interest in riding the shovel or twincam.......dam i always wondered what a real harley (f head or flathead) would feel like.........it's addicting!...............thanks mark
Re: mallory timer, advance curve
This is the type of thread that makes this message board SO COOL !
Re: mallory timer, advance curve
John
Agreed.
Mods
Please strive to keep the forum about the bikes. There are many other forums out there for the people aspect.
Thanks
F
Agreed.
Mods
Please strive to keep the forum about the bikes. There are many other forums out there for the people aspect.
Thanks
F
Re: mallory timer, advance curve
fhsmith1 wrote:Mods
Please strive to keep the forum about the bikes. There are many other forums out there for the people aspect.
Thanks
F
??????????????????????????????????????????????
Re: mallory timer, advance curve
I'm not seeing what the "Mods" reference is to, either ...
Mark
Mark
Re: mallory timer, advance curve
I assume "Mods" is moderators but I still have the ?????????????????????????
Re: mallory timer, advance curve
moderators.
Yes, that's what I was refering to. Sorry for the confusion.
F
Yes, that's what I was refering to. Sorry for the confusion.
F
Re: mallory timer, advance curve
It is the rest of the post I do not understand.
Re: mallory timer, advance curve
Pa
I was involved in a thread a couple of years ago that started out very constructive but got away from anything to do with motorcycles. The thread got to be just a pissing contest between 2 or 3 people. The instigator was asked to leave. I thanked the moderators at the time and thank them again. That's all.
F
I was involved in a thread a couple of years ago that started out very constructive but got away from anything to do with motorcycles. The thread got to be just a pissing contest between 2 or 3 people. The instigator was asked to leave. I thanked the moderators at the time and thank them again. That's all.
F
Re: mallory timer, advance curve
Thanks...we have had a few feuds here in the past that is for certain.
Re: mallory timer, advance curve
FHsmith, just rereading one of your posts where you mention modifying a Sporty timer for use with your flatty. I presume you figured a way to limit the amount of advance the timer has? If so, how'd you do that?
Thanks,
DD
Thanks,
DD
Re: mallory timer, advance curve
DD,
I found it very easy to alter the max advance by pushing out the roll pins in the weights, and drilling them out for larger pins. The pin limits the advance by stopping on the side of the hole in the weight base.
I found it very easy to alter the max advance by pushing out the roll pins in the weights, and drilling them out for larger pins. The pin limits the advance by stopping on the side of the hole in the weight base.
Re: mallory timer, advance curve
DD
That's almost exactly what I did. I punched out the pin, threaded the hole and loctited a 1/4" X 28 bolt. I left the unthreaded portion sticking out the same amount the roll pin did. I then drilled out the correponding hole in small increments until I got the desired results.
F
That's almost exactly what I did. I punched out the pin, threaded the hole and loctited a 1/4" X 28 bolt. I left the unthreaded portion sticking out the same amount the roll pin did. I then drilled out the correponding hole in small increments until I got the desired results.
F
Re: mallory timer, advance curve
Thanks guys, That makes sense. I'd been looking at the hole and trying to determine how to make the hole smaller. Like the roll pin trick, we've got a wide selection over at the gun shop, I'll try that one first!
Thanks,
DD
Thanks,
DD
Re: mallory timer, advance curve
The trick we always did in the '70s was to slip a snug fitting spring over the pin, restricting travel. I believe they were Sportster shifter pawl springs.
Robbie
Robbie
Re: mallory timer, advance curve
DD,
If memory serves, a roll pin 1/64 larger than stock brought the advance close to the right number for flatties.
If memory serves, a roll pin 1/64 larger than stock brought the advance close to the right number for flatties.
Re: mallory timer, advance curve
All
Same things works good for a double plugged head shovelhead. Especially if you want to kick start it.
F
Same things works good for a double plugged head shovelhead. Especially if you want to kick start it.
F
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