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Anyone here very knowledgeable on the WB 700?

Seems like they're not talked about as much as the 610 or 820.

What is the story on this engine?

Thanks

Hi, John. There are many out there who know lots more about the 700 than I do. Here goes, anyway. It's a chrome bore, cross-scavenged (deflector top piston) mill with 7.0 C.I.. It produced about
5-1/2 - 6 H.P. and was a lower RPM engine than the 820, which is loop scavenged. Lots of torque, and not a lot of horsepower unless highly modified. There was a later 5-port version which had 2 extra intake ports arranged in a semi-loop scavenged scenario. Put out some extra H.P. and RPM, but nowhere near as much as the 820. The 700 and 580 were earlier designs than the 820 and 610's. They're very strong and reliable and a great choice for an early ('57-'59) kart. More, anybody? Ted

The 580 and 700 were really kind of the foundation of karting. As you can read on this web site, Art Ingels used a little bender on his very first kart (though it was marketed as a McCulloch engine - note the yellow paint).

The 580 was a great industrial engine and was used on chain saws, cmpactors, post-hole augers, and just about anything elese you could imagine. In addition, the various versions of the engine were used on outboard motos, including the 5-Port 700.

I ran a V-700 on a minibike in 1960 and 1961 and as I recall it produced 10 ft-lbs of torque at 3000 rpm - meaning that it got off the line really quickly. I later drove a home-built kart with a 5-Port 700. Scared me half to death as it really would roll. Maybe it was the lack of suitable brakes................

These engines were very, very reliable. I don't ever remember having a minute's problem with my V-700 engine, and it always started on one or two pulls, and idled like a dream.

Of course it was an old design with the cylinder head integral with the cylinder, so it was physically strong but hard to play with compression ratios. If you look at the 610's and 820's, they really follow the overall layout of the McCulloch engines pretty closely what with a demountable cylinder head and the arrangement of the cooling air shrouds. Not hard to confuse a Mac 101 and an 820 if they are painted out in non-traditional colors. The 820's were a bit heftier, in keeping with their tradition of being nearly indestructible.

The key thing for us vintage racers is that the 580, 700 and the 820 continued in production as industrial engines long after they fell out of favor as kart engines, making them a bit easier (and cheaper) to come by. I've seen the 820's as ultralight engines, fire pump engines, and they were used for years on the Chrysler Sno Runner (a sort of snowmobile) and the Rokon 2-wheel-drive off-road utility motorcycle.

From what I can tell from the old karting mags, the 820 was a competitive equal to the 101.

That's everything in my brain.........

That's great!

Thanks