Mac 49ers

[mcbob]

Well fellas having zero experiance with this model i have a need to be enlightened we're they 80 or 87cc and will they handle the BDC 14 and BDC 16 carbs any other info that would be useful would be nice.

McBob

[justin_cosgrove]

Hi ya Bob,

the 49 is a 80cc, maybe the variants could have been 87cc kinda like how the 250 saw is a 80cc but the super was 87cc.
Other than that I'm in the same boat as you and also want to learn more about these motors as I have a couple. The MC-49s weren't raced in Australia or here in New Zealand so nobody in these parts seems to know much.

Justin

[Dick Teal]

Guys,

When the first Mc49 engines became available Don Fairman (Brodhead, WI sprint track) started a class for kids. I had two boys that were the correct age and they raced the class for a few years. The rules were stock engines with box mufflers and gas fuel. The class was extremely successful and he eventually created a dual 49 class.

The engines are very durable when left stock and they run for years of racing. I think that's one of the reasons the vintage events are seeing a growing population of them.

I haven't seen one with the large carb on it but it will probably work. I would guess that the low end torque would be pretty bad. I use a 1" bore alcohol carb on the engine I race and the low end is pretty bad but the high end is fantastic. I use a 6000 rpm clutch but I need at least another 1000 to get the low end better. I think that you'll be surprised by the power and performance of the engine even in it's stock form.

It looks like the rules for vintage here in the states will stay pretty simple. We require a box muffler and a single carb with 1" bore or less. We don't check fuel or other stuff because most of us just want to race and to keep it simple. If you run alcohol and mess with the timing you can notice a marked improvement in performance.

Try them and you will like them and you'll have a lot of fun.

Dick Teal

[Scott Kneisel]

I have a nice 49C that I built up for my wife. It isn't stock though, I did some porting and punched it out to 0.040" oversize. I used a Mac 450 saw piston with the correct pin to crown measurement so it would clear the head. I am using an Mc45 manifold with go power reed block and a tilly HL250 carb which has a 1" throttle bore. I am running gas and it has surprising power and will run flat out all day. To get the low end I am running tall gears to make that hairpin at Avon but it still winds all the way down the straight.

The track owner at Avon (Al) told me that back in the day when his kids ran in the 49er class, he doped the fuel with Nitro and some other stuff and could make them fly. I wouldn't want to do that but might try alky and some advanced timing 5degree flywheel style!!

I will have the 49er on my 63 grand prix at TBO for the first day. Should be fun.

[mcbob]

Well fellas thanks for your answers and you's are right on the engines sizes imagine we have tons of these sizes floating around here in Aus so i might see if i can get a little interest going in an 80cc hotsaw class and get old Mac's in another class at our races. It amazed me how much interest i got when we flogged all the current Stihls and Husqvarnas hotsaws with our vintage SP125c at Dungog which hosted our Saw Nationals it's something that upset the old apple kart.
Thanks Louie for the email stuff as i had lost your email address and haven't been able to yap with ya but i'm back now just like old Arnie.

McBob