Which is more reliable semi auto or just auto?
 

We are thinking of upgrade the 110 mini hummer to a 125 (not because of the engine size but more of a wider stance little bigger bike) for our 7 years old.

The question is we can get the semi auto (3-2-1-N-R) or the auto (F-N-R) for same price and I know the 3 speed one should give slightly better performance but its the reliability that I am more concern with.

Anybody, has experience with these tranny please chime in.

Thank you in advance!

Personally, I really like a semi auto transmission. In general they are bullet proof and maintenance free. Most autos (except Hondas) are belt driven. The belts will wear out and need to be replaced and if they get wet will slip and you will go no where. It would also be good to teach your 7 year old about shifting. Some day they might want a sport quad with a manual transmission and the semi auto would at least be some training.

Eventually no one will know how to use a manual transmission, on ATVs or cars. Everything that is coming out seems to be automatic. I wish they would come out with some semi auto transmissions on bigger bore ATVs. That is my rant. Hope it helps.

The only thing I would caution about the 3 speed is most if not all of them have a very high(almost useless) 3rd gear... Something about the real 3rd gear space being used for reverse... so the 3rd is actually a 4th gear..

Thank for the post / reply!

Is this auto tranny with the reverse (F-N-R) any difference between 125cc and 110cc without reverse?

The reason I ask is on our 110cc (auto) its only a single speed and it is not really a transmission it just one speed with a centrifugal clutch,no?


Thanks again!

I have to agree with MWQ the 3 speed tranny in these things would be way better as a 4 speed. As sometimes 1st is too high.

As for the Auto's there are 2 kinds in these little quads. One that is internal built into the trans, and the CVT type using a belt mounted on the side of the engine. The CVT type on the 150 quad we have works excellent. We haven't had any issues with it what so ever. I pulled the cover off to check the belt here after 2 years and it still looked like new.

My Yamaha is CVT and yes at times it would be nice to have the old gear shifter but the CVT works good too on it.

Right. That's all it is. A wet centrifugal clutch. As far as reliability is concerned, this setup has the fewest parts, so fundamentally it *should* be the most reliable. For a kiddie machine, they're perfect. For older kids and adults, they'd probably burn the clutch out early because they are kind of like a 4spd semi auto, stuck in 2nd. My kids ATV has the 'single speed'. It will haul my 225lb self easily, but obviously couldn't take off very loaded, nor will the top end speed be much. Not having neutral is a pain, you just have to lock the brake to blip the throttle, or lift the arse end off the ground to rev it for troubleshooting, etc..

Joel

Thanks for all the post and info gentleman!

If the 3rd gear is geared so high and not much use anybody has ever try change the front sprocket to a smaller one?

Will it work?

3rd gear would probably be doggy on a 110cc with a 220lb driver on it, but I'd imagine it would be great for a kit.

Joel