Dolmar 64xx/73xx/79xx series, smurfs and solo 665/675/681 thread

[huskihl]

So if I can help it, keep it closer to 80.

And do you suggest more than 28 degrees blow down?

I get the transfers and staggering them.

Everyone's opinion is different. I like 28, so I go 26 on the mains and 30 on secondaries. But you'd be hard pressed to tell the difference between the above numbers and 28 and 32. Or 30-34 for the guys who have trouble raising them. Numbers are really just that. I see more differences in shapes and contouring

 

[mettee]

So hit the numbers but really look at flow. I was thinking the transition out of the uppers was super important...How they direct the charge.

 

[thedude74]

Is it ok to beat a dead horse? One that's been beat to death and beyond for almost a decade now.

Yes it's the infamous Dolkita BBK question. I understand the quality is not nearly what the Mahle is. However, has anyone had failures? Stock 79xx vs 84bbk sounds like they make similar power depending on kit. I noticed on flea bay a seller out of Greece has 52 mm and 54 mm chrome lined after market kits for Smurfs and red non Smurfs. Yes, I'm a cheap bastard in general but thinking if I'm going to grind on a cylinder and potentially screw it up perhaps $100 vs$220 might be the way to go.
Can the bbk be cleaned up and made into a dependable runner for a firewood hack?
Thoughts? Experiences? Ideas? Sasquatch stories(those are cool too)?

 

[Fruecrue]

Is it ok to beat a dead horse? One that's been beat to death and beyond for almost a decade now.

Yes it's the infamous Dolkita BBK question. I understand the quality is not nearly what the Mahle is. However, has anyone had failures? Stock 79xx vs 84bbk sounds like they make similar power depending on kit. I noticed on flea bay a seller out of Greece has 52 mm and 54 mm chrome lined after market kits for Smurfs and red non Smurfs. Yes, I'm a cheap bastard in general but thinking if I'm going to grind on a cylinder and potentially screw it up perhaps $100 vs$220 might be the way to go.
Can the bbk be cleaned up and made into a dependable runner for a firewood hack?
Thoughts? Experiences? Ideas? Sasquatch stories(those are cool too)?

@SOS Ridgerider found a killer deal on an OEM 52mm top end recently. Mayhaps Thunder will come along and share a link.

This one time, a Sasquatch......

 

[Rob Stafari]

https://sleequipment.com/makita-genuine-part-038-130-070-cylinder-piston-cpl-dcs7901.html

There’s the link @SOS Ridgerider posted. I still have it open with a couple in a cart ready to go. Apparently it is the original 7901 cylinder with the updated 7910 piston? If I remember/read correctly.

100 vs 150 is a whole different decision to make than 100 vs 220.

 

[SOS Ridgerider]

@SOS Ridgerider found a killer deal on an OEM 52mm top end recently. Mayhaps Thunder will come along and share a link.

This one time, a Sasquatch......

Was his name Phil Cosby???

https://sleequipment.com/makita-genuine-part-038-130-070-cylinder-piston-cpl-dcs7901.html

There’s the link @SOS Ridgerider posted. I still have it open with a couple in a cart ready to go. Apparently it is the original 7901 cylinder with the updated 7910 piston? If I remember/read correctly.

100 vs 150 is a whole different decision to make than 100 vs 220.

That’s the one. Yes, 7900 cylinder with a 7910 piston. Best of both worlds, especially if you have the old top cover with the flywheel side decomp. Or, if you’re trying to make an old school red top looking saw, like I was.
I bought two of those top ends. The price is right. I’m keeping one as a spare. You never know when you’ll stumble upon another saw that needs a little boost

For the gentleman asking about the BBK; I had a saw with a BBK that ran pretty good, which I sold, and I have two more top ends sitting here just in case I find a beater saw to put one on. Currently I have another AM kit on a saw, and it’s meh...
If you’re looking into porting it, the oem kit will have quite a bit more potential for gains. The transfers on the 54mm BBK are quite small, due to bigger bore, than the oem 52mm ones. This is only what I’ve heard from guys that have ported them, but I have no reason to doubt what they’re saying.

One of those oem top ends is now installed on this previously 6421. Put it all together the last couple of days. We’ll try it out at the CT GTG this weekend.


On a side note, this is how much crap that’s in the muffler on the 6421s. It’s actually quite a bit of weight. I was a little surprised it was that much.

 

[Fruecrue]

Was his name Phil Cosby???

OMG, how did you know?
Good looking saw there, how’s the new shop treating you?

 

[SOS Ridgerider]

OMG, how did you know?
Good looking saw there, how’s the new shop treating you?

Me and old Phil go way back. Creeper style.

Thanks, it came out decent. New shop is great! It’s awesome to have a nice place to work in. I was getting tired of the damn garage. Lol

 

[Yotaismygame]

That’s a good price on the oem top end. But I’ve got a 10% off coupon for saw again and their same top end is $190. I’ll stick with them.

Did you see my recent post of the BBK saw I have? Go back a few pages. Runs great with a gutted muffler. I have about 10 tanks through it.

Has any one else noticed hyway now makes a 54mm Makita top end? I find hyway stuff to be pretty good quality.

http://www.sawagain.com/hyway-54mm-...ar-ps-7900-ps-7300-makita-dcs-6401-6400-6421/

 

[thedude74]

https://sleequipment.com/makita-genuine-part-038-130-070-cylinder-piston-cpl-dcs7901.html

There’s the link @SOS Ridgerider posted. I still have it open with a couple in a cart ready to go. Apparently it is the original 7901 cylinder with the updated 7910 piston? If I remember/read correctly.

100 vs 150 is a whole different decision to make than 100 vs 220.

That's quite a deal! Dang it. Too close in price not to go oem. 79 cc of wood chipping glory. The spruce trees on my property look nervous.

 

[Yotaismygame]

It’s decent deal. Says $18 to ship. Little cheaper than most places.

 

[Yotaismygame]

Got a smoking deal on this today. It’s almost new! Gunna work some magic on her and let her fly.

 

[PA Dan]

Back in November when I got my 6421 they had the 7910 cylinder kit for that price. It was $166 to my door. I couldn't find any place close to that. They drop ship from Makita.

 

[SOS Ridgerider]

That's quite a deal! Dang it. Too close in price not to go oem. 79 cc of wood chipping glory. The spruce trees on my property look nervous.

You won’t regret going oem. That’s a sweet top end. I see in your signature you have 2 6401s. The stock plastics should fit right on. Like a glove!

 

[dahmer]

You won’t regret going oem. That’s a sweet top end. I see in your signature you have 2 6401s. The stock plastics should fit right on. Like a glove!

Aren’t the decomp valves on different sides? My old mind can’t remember but thought I had to swap engine cowl once.

 

[PA Dan]

Aren’t the decomp valves on different sides? My old mind can’t remember but thought I had to swap engine cowl once.

For the 7910 you do!

 

[SOS Ridgerider]

Aren’t the decomp valves on different sides? My old mind can’t remember but thought I had to swap engine cowl once.

For the 7910 you do!

Dan is right. The 6401 had the decomp on the flywheel side, so this top end will fit right on and can use the stock cover. If it had been a 7910 top end you’d need a different top cover.
The decomp itself is also different between the flywheel side models and the pto side ones.
@thedude74 doesn't have to worry about any of this if he gets the top end in the link @Rob Stafari posted.

 

[thedude74]

Dan is right. The 6401 had the decomp on the flywheel side, so this top end will fit right on and can use the stock cover. If it had been a 7910 top end you’d need a different top cover.
The decomp itself is also different between the flywheel side models and the pto side ones.
@thedude74 doesn't have to worry about any of this if he gets the top end in the link @Rob Stafari posted.

Very helpful info guys. I knew they switched the decomp to the other side on later models but no idea the decomp itself was different. You guys rock!

 

[tickbitintn]

Very helpful info guys. I knew they switched the decomp to the other side on later models but no idea the decomp itself was different. You guys rock!

I got one of those. Plug and play. You won't be disappointed.
Thanks again @SOS Ridgerider

Sent from my XT1635-01 using Tapatalk

 

[huskyboy]

I ordered new springs for my 6421 clutch that needed them. Old ones shot, but clutch itself in great condition. Very easy to replace them, no special BS tools needed. The new updated coil springs have one more coil and are quite a bit stronger than the originals. I got a new washer too. New Old style