The Unlimited Dolmar 7900

[David Young]

I think the over rev is handy for knot bumping. And can’t racing

Like the rev boost. But I think 15 k would be a good limit

 

[Hedgerow]

I just cut firewood... I was replying to the guy who just has a muffler mod, not to the guys racing saws.

The 7900’s want to run higher than the stupid assed limited coils they come with.

That being said, the 13,600 coils have a good advance you can work with..

That 12,900 coil is the stupidest thing ever.

 

[Hedgerow]

@Hedgerow runs the Mutt with a limited coil. Have fun beatin him.

But there again, operator and chain...

Unlimited coil with the same advance would sure make my life better.
Cuz I gotta tune way the hell past the limiter.

By sound and throttle response.

How fast does it hit the limiter.??

 

[Deets066]

Wanna race?.

Sure do

 

[Deets066]

Wanna race?.

Ur chain gunna stay in one piece?
And tensioned?

 

[P.M.P.]

Anybody near Newport News VA? That's the last spot that coil was known to exist.

Finding this coil could be as hard as Someone looking for a stolen Rembrandt painting FFS

 

[Leafy]

This shouldn't be that hard to get copies made of since you're a company. Make a physical drawing of the coil. Put a timing light on a stock coil to see what the peak advance is and the starting advance. Send to China coil supplier you find on alibaba, include instructions that it should retard timing below 3k rpm to whatever you found to aid starting and it shouldn't retard timing about that. You have to agree to buy like 1k of them at like 4 dollars a piece. The mane you samples in a couple months for you to test and you'll either be happy and get the 1k production run or you'll give them feedback and they'll make changes and send more samples.

If you need someone to make a drawing of the coil that looks like an actual engineer did it, I'm your guy.

 

[AlfA01]

The 7900’s want to run higher than the stupid assed limited coils they come with.

That being said, the 13,600 coils have a good advance you can work with..

That 12,900 coil is the stupidest thing ever.

Which one is which? Part # and color wise? I have a red lead, maroon coil in a 2007 Dolly 6400 converted with 7910 P&C. I'm assuming it's 13,5/6K as the 'tell tale' tach will hit over 13K piss revving. I haven't pushed it to see what the limit is.

I wonder if there were any geographical differences with these models.

 

[Redfin]

Ur chain gunna stay in one piece?
And tensioned?

Who cares. Dis be a race to mount a coil.

 

[Mastermind]

This shouldn't be that hard to get copies made of since you're a company. Make a physical drawing of the coil. Put a timing light on a stock coil to see what the peak advance is and the starting advance. Send to China coil supplier you find on alibaba, include instructions that it should retard timing below 3k rpm to whatever you found to aid starting and it shouldn't retard timing about that. You have to agree to buy like 1k of them at like 4 dollars a piece. The mane you samples in a couple months for you to test and you'll either be happy and get the 1k production run or you'll give them feedback and they'll make changes and send more samples.

If you need someone to make a drawing of the coil that looks like an actual engineer did it, I'm your guy.

Bruce sent a limited coil to Chinese manufacturer. Just asked that it be the same without a limit. They were no help. Nothing but "we copy" "no changes".

Finally gave up.

 

[Leafy]

Wtf. If I cared enough I could design the circuit. I think your best bet for this right now is just to de-pot a limited one and remove the rev limit circuit. Unless it actually uses a microprocessor then it's much harder.

 

[Mastermind]

Wtf. If I cared enough I could design the circuit. I think your best bet for this right now is just to de-pot a limited one and remove the rev limit circuit. Unless it actually uses a microprocessor then it's much harder.

This was sort of my last ditch effort. I'm gonna just move on.

 

[Cut4fun]

The old thread here. http://opeforum.com/threads/dolmar-7900-coil.42/

Figured someone would have had one made up by now.

 

[Dub11]

Bruce sent a limited coil to Chinese manufacturer. Just asked that it be the same without a limit. They were no help. Nothing but "we copy" "no changes".

Finally gave up.

On a side note can you tell them little fellers over there to copy stuff more better consistently please?

 

[Hedgerow]

Which one is which? Part # and color wise? I have a red lead, maroon coil in a 2007 Dolly 6400 converted with 7910 P&C. I'm assuming it's 13,5/6K as the 'tell tale' tach will hit over 13K piss revving. I haven't pushed it to see what the limit is.

I wonder if there were any geographical differences with these models.

Yes. Maroon one is best functioning one I've found thus far.

The unlimited one on Deets' Solo works well though. Not sure what he stole that one off of. 272 coil maybe?
And since it still is working, it must be OEM.. Lol.

 

[T.Roller]

Which one is which? Part # and color wise? I have a red lead, maroon coil in a 2007 Dolly 6400 converted with 7910 P&C. I'm assuming it's 13,5/6K as the 'tell tale' tach will hit over 13K piss revving. I haven't pushed it to see what the limit is.

I wonder if there were any geographical differences with these models.

That is the one you want. I swapped out the 12.8 coil on mine for the maroon 6400 coil. Much better.

 

[mdavlee]

Unlimited coil with the same advance would sure make my life better.
Cuz I gotta tune way the hell past the limiter.

By sound and throttle response.

How fast does it hit the limiter.??

That saw stays on the limiter unless loaded real good. Some hack got lucky when he ground on it

 

[Redfin]

The red coil is the higher limited between the that and the black?

 

[Deets066]

The unlimited one on Deets' Solo works well though. Not sure what he stole that one off of. 272 coil maybe?
And since it still is working, it must be OEM.. Lol.

Yes 272
Yes oem

 

[Deets066]

Dis be a race to mount a coil.

Can I cheat?