I think it refers to having a bearing at both ends of the crankshaft rather than just one. This would imply a more durable and heavy duty design with full crank.

You simply will not find a half crank that fits into the medium to heavy duty class. Half cranks are generally considered cheap throw aways. That's not to say they don't have a place in the market, they certainly do. Many home users on a tight budget find these to be a good fit. But they will never be considered a quality unit.

Hello all.

Thanks for the info fordtech and nevada walrus. I've got my thinking cap on straight now.

Good day

Right, and it ultimately affects not the internal design but also the starter setup. Because a "half-crank" only has that single crankcase exit, you'll find the starter for it buried in the drive shaft's PTO side. That makes it virtually a complete disassembly just to replace the recoil starter. Ergo, it's throw-away if you break the cord or otherwise screw up the starter. On all full-shaft models, you'll find the starter on the back of the engine, the opposite of the shaft PTO. Replacing the recoil unit on these is basically just a four-screws process. So the visual giveaway to whether a trimmer is "full" or "half" shaft is the location of the starter.

Hello all.

Home run mattv21!
Thanks for that information.

Good day.

Had a half-crank Troy Bilt for 3 years, replaced it today with a full-crank Echo. Extra heft in the crankshaft isn't the only thing they skimp out on. The Echo manual actually lists maintenance intervals, procedures and part numbers. The Troy Bilt's manual has none of those things because it's assumed it'll be on the curb before any maintenance is necessary.

I have two SRM2600 Echo that are getting quite old. They still run like new and I wouldnt trade them worn out for 4 brand new economy models. I dont think you can kill these bad boys.

I have both Echo and Shindaiwa full crank trimmers and a Ryan (Lawn-Boy) half crank unit. The full crank models are smoother, start easier, just better all the way around than the half crank unit. Echo and Shindaiwa are 300 hour rated engines, most half crank engines are rated 50 hours. The best value in a trimmer are the straight shaft Echo units bought from a service providing dealer IMHO.

I've had a 'half-crank' Ryobi 725r for 14 years with no problems in light homeowner use. It's the 'Click-Link' and I have the blower head, so it's my trimmer and blower. If anything happened to it I'd get another one if I could still find a new one. It doesn't have the 'dead-man' switch like the new ones that you have to hold down.

I havent looked at any new ones lately and was unaware of a deadman switch. It hurts the arthritis enough as it is to hold that thing at an angle for long periods of time without that hassle added in.

And how about that goofy extra chain brake on the new chainsaws? My neighbor got a new saw and asked me to fire it up for him. I didn't know about the brake you have to release, but got the engine started anyway. When smoke started coming up off the brake, I knew something was bad wrong! I guess it's a kickback brake.

IIRC the deadman switch he's talking about is just a grip safety, like a Colt pistol. It's so the throttle can't be goosed unless you're holding the trimmer. They're removable, by the way.

I usually won't go near low-end trimmers any more (especially Ryobis, I hate working on those) but I have to speak up for the older Homelite 25cc half-crank trimmers. They're _not_ commercial duty, but every one I've owned or worked on has been nails. I got my first one (used) out of a trash bin in 1998 or so, used it for a few different lawns for 8 years, and sold it to a guy who does 12 lawns a week and it's still runnning like new.

Of course now that I'm running a Stihl FS-74 I can't say I miss the Homelite.

Well. It looks like Ryobi stopped making 2 cycle 1/2 crank engines. All the new ones are full crank. They lowered the cc also.

The new carburetors do not have a idle jet adjustment.

The newer carburetors have jet needle that lifts with the throttle.

I will be getting 2 of them next week to test.

I will keep everyone informed.

The thread is 10 years old. However, do make sure you understand the vibration that can come from these "less supported" designs. It can be miserable after an hour of usage.

Wow, 10 years. It seems like yesterday.. LOL and Im still using my Echo SRM2601 trimmers I bought well used years before I posted on this thread 10 years ago. :)

And I have gone from homelite to stihl to 58v battery powered trimmers.

I did eventually buy a new Ryobi but there was no problem with the reciprocating engine parts - the carb went bad and I hate trying to work on these little square carbs. Anyway the matter was settled as to the crankshaft because the new Ryobis are full-shaft

1. Speaking of kickback lmao . Even the old half crank weedeaters if serviced well would last yrs under light service usage . Not a commercial grade unit but as a homeowner unit they would get the job done but yes vibration would be noticeable lol .

Well. so far I am impressed. I will be doing some real tests in the spring. Both start, run and idle fine. I did not see any difference in the lower cc. It is a little heavier. The starting method is different you need to hold the throttle. If the pull starter needs to be serviced that will be no problem. They also have a better clutch than the older 30cc units. I bought these on a Black Friday deal. They were the so called refurbished, which as far as I can tell they are new. These only have a 1 year warranty. I paid $59 each and no shipping charge.