70cc class Dyno day

[MustangMike]

Is the dolmar a fair amount heavier? Just asking because I’ve never ran a 7900 dolmar is non existent up here

YES! I'll let Joe post the #s, but I believe it is over a pound.

 

[Red97]

YES! I'll let Joe post the #s, but I believe it is over a pound.

Once I get them all here I will weigh them all out of the box full of fluids then dyno runs.

Going to try and hit all the classes.

 

[Wanab]

I might know a feller who just found a pretty mint low hour 7900

Papa Smurf wants to play, thinks he can knock that 500i off it's pedestal.

 

[huskyboy]

Papa Smurf wants to play, thinks he can knock that 500i off it's pedestal.

View attachment 316731

The 500i was on a pedestal? Lol

 

[huskihl]

Papa Smurf wants to play, thinks he can knock that 500i off it's pedestal.

View attachment 316731

I don’t think there’s a 500i on the pedestal. The strongest 5 cube on the dyno so far was an 044/046 hybrid I believe.

 

[Red97]

Papa Smurf wants to play, thinks he can knock that 500i off it's pedestal.

View attachment 316731

Send it in. I can turn around dyno runs pretty quick.

 

[Woodpecker]

Papa Smurf wants to play, thinks he can knock that 500i off it's pedestal.

View attachment 316731

Everyone knows I love a good 7900/10, but it would have to be pretty special to beat a hybrid in the hp department.

 

[Wanab]

The 500i was on a pedestal? Lol

Fur' $2200 it comes with one...

https://www.ebay.com/itm/2036900653...ZzVwrt94xmvGgK5zG5cCUWYnND2B4DPRoCeUwQAvD_BwE

 

[andyshine77]

I was just wondering if you ever got around to running a proper stock 7900 on your contraption? According to the wood dyno with broken-in saws the 500i has nothing on it.

The 500i has a little more in it and will pull an 8 pin better. Some of the 7900's were nice and hot from the factory around that time. The saw in the video has 190 pounds of compression and very tight squish from the factory, the tightest I've ever seen in fact, you can get away with that on the 7900. I originally was going to port it, but it runs so well I thought better and just keep this one as is. The 7900 was one hell of an engine design.

 

[Dieselshawn]

Somehow I missed this thread. Just started reading it. Terrible on my part.

 

[Dieselshawn]

I'm kind of hoping Makita does the right thing and sells Dolmar rather than just quietly sweeping the company under the rug... Be really cool if a company not named Husqvarna bought it.

I realize that this is a one year old post but I’ve noticed Husqvarna has been buying up a lot of companies besides Ope stuff.

 

[huskyboy]

The 500i don’t make much high rpm power stock. Narrow powerband (about 7500 - 9500rpm). Gotta gear them up to 8 pin or just tune the chain to the saw better with a 7 pin. Got to make up for the lack of rpms if you want to cut small-medium sized wood more efficiently without it bumping the rev limiter slowing it down constantly lol. The peak torque for the displacement really is amazing once you load them in a real piece of wood with a longer bar though.

 

[andyshine77]

The 500i don’t make much high rpm power stock. Narrow powerband (about 7500 - 9500rpm). Gotta gear them up to 8 pin or just tune the chain to the saw better with a 7 pin. Got to make up for the lack of rpms if you want to cut small-medium sized wood more efficiently without it bumping the rev limiter slowing it down constantly lol. The peak torque for the displacement really is amazing once you load them in a real piece of wood with a longer bar though.

I do agree.

However "playing the Devil's Advocate as I tend to do" I think the 500i spins faster than we think it does, the sound is throwing us off and skewing our perception a bit. The fact it doesn't it doesn't pull down as fast factors in too I believe. I have the printout from my dealer and maximum RPM on my 500i was 14,150 so she can spin. Before I really started timing things I always thought my ported 372 was faster than my ported 7900, our perception is very powerful and is why testing in the wood, or even better on a Dyno, takes our perception out of that equation.

 

[Nutball]

I realize that this is a one year old post but I’ve noticed Husqvarna has been buying up a lot of companies besides Ope stuff.

Chainsaws wasn't their first line of business was it? I know they've been in motorcycles & sewing machines for a while.

 

[Woodpecker]

Chainsaws wasn't their first line of business was it? I know they've been in motorcycles & sewing machines for a while.

It was guns originally I think

 

[Duce]

Vacuum cleaners also.

 

[Dieselshawn]

Chainsaws wasn't their first line of business was it? I know they've been in motorcycles & sewing machines for a while.

We have Husqvarna concrete floor grinders and polishers.

We also have HTC and Diamatic as well.

Husqvarna bought them all out in a short time.

My favorite machine is Diamatic as they have power to seriously grind hard to remove stuff.

Husqvarna 820 remote controlled grinder with large Husqvarna vacuum and dust collector combo.


Here’s the 780 Diamatic I use. It’s a manual push/pull machine. No remote. Also loaded with four 100 lb tractor weights.

 

[Catman]

We have Husqvarna concrete floor grinders and polishers.

We also have HTC and Diamatic as well.

Husqvarna bought them all out in a short time.

My favorite machine is Diamatic as they have power to seriously grind hard to remove stuff.

Husqvarna 820 remote controlled grinder with large Husqvarna vacuum and dust collector combo.
View attachment 316920

Here’s the 780 Diamatic I use. It’s a manual push/pull machine. No remote. Also loaded with four 100 lb tractor weights.
View attachment 316922 View attachment 316921

Do they use carbide to cut with?

 

[Dieselshawn]

Do they use carbide to cut with?

Diamond cutters and also carbide depending on the job.


This is carbide. For cutting coating off.



These are diamond cutters. Comes in many forms and grits.


Then after the diamonds have finished, we use resin diamonds from 100 grit up to 3000 grit to polish concrete to a high finish or shine.

 

[Catman]

Diamond cutters and also carbide depending on the job.


This is carbide. For cutting coating off.
View attachment 316944


These are diamond cutters. Comes in many forms and grits.
View attachment 316945

Then after the diamonds have finished, we use resin diamonds from 100 grit up to 3000 grit to polish concrete to a high finish or shine.

View attachment 316946 View attachment 316947

That’s Awesome brother!