How to control speed on a quad

iwb

I have an 80cc Suzuki quad and the kids use it. I would feel a lot safer if it didn't go so fast. Limiting the throttle travel doesn't do it as it won't go up hill then and still goes too fast at times. Is there some sort of after market unit that will measure the speed of the quad and cut the spark over that speed?

madrab

I dont mean to lecture but...
just dont let them on it, quads are not meant for kids. a young kid down the road from me nearly lost his foot from messin on a quad.

iwb

Thanks for the input. I have thought about it quite a bit. They are over 12, as it says on the safety warning on the machine but that is hardly the only point.
I know they could be injured on it but there are so many potential sources of injury, it is hard to know what to allow them to do or use. As a parent, it is a very difficult thing to decide and be happy with.
I really don't want to wrap them in cotton wool. They definately won't be very well prepared for life That way. I have seen people like that and I think that was worse than letting them take some risks.

Wossack

this may sound like a really stupid idea, and please if it's mechanically dangerous etc etc someone please interject

but could you increase the slack a fair bit on the throttle cable? so that when it feels like its fully open, its actually only half? or does the throttle (on the handlebars) freely rotate, and effectively 'reel-in' this slack, and change nothing? got issues with the long loose loop possibly snagging near the engine etc too... as I said, big big grain of salt with this one

failing that, fill the tyres with cement, or go mad with duct tape and cinder blocks, attach a sled like they do with tractor pull...

more realistically, if you can get it to a bike shop, Im sure they can restrict it for you, and have more, erm, mainstream methods of doing so :P

iwb

I can limit throttle travel and that is how it is done now. This isn't suitable because as mentioned above, it means the machine won't really go uphill. With the bigger kids, it won't pull them up the hill but it goes too fast downhill.
I had a jetski years ago and the rev limiter was a very simple affair. It was a small sealed unit which cut the spark over a certain rev limit. The same could be done here but with wheel revs rather than engine revs. The big advantage is that it doesn't limit power, just speed.

Pigeon Reaper

is it carbed or fuel injected?

iwb

How will I tell that?

Pigeon Reaper

well if it's carbed which it probably is you could change the jet size or limit the slider so it won't rev too highly. If you don't know what to look for you're better off leaving it alone.

Oryx

I know its done in the carb, as well as the throttle. We use them and I know my hb adjusts the speed to suit the child. Im going to have to ask him how its done and get back to you tho.


[Lecture]Safety has been mentioned, and Ive just got to mention... A properly fastened helmet is essential[/Lecture]

Del2005

KtK wrote:

I know its done in the carb, as well as the throttle. We use them and I know my hb adjusts the speed to suit the child. Im going to have to ask him how its done and get back to you tho.


[Lecture]Safety has been mentioned, and Ive just got to mention... A properly fastened helmet is essential[/Lecture]

And proper offroad motorbike boots and body armour. Don't won't them breaking bones when they fall off. If they have all the proper safety equipment then the speed shouldn't be an issue. AFAIK all restictors fitted limit power as a limit on top speed would require a feed from the gearbox/wheels. Maybe check the Suzuki website to see if they have a way of restricting speed built in already.

galwaytt

madrab wrote:

I dont mean to lecture but...
just dont let them on it, quads are not meant for kids. a young kid down the road from me nearly lost his foot from messin on a quad.

have to disagree with you there, I have two kids, one boy(4), one girl (7), and we've had a quad for 2 years. He's been driving it for nearly a year, and she's now moved up to a Honda 50cc motorbike. I don't go for the cotton wool approach, and both machines ARE made for kids. They're not allowed out, unsupervised, and always wear gear.

Restricting the carb etc, won't work - the Quad we have is the same problem, with a carb restriction it won't rev enough to engage the automatic clutch on hills, or in ruts, etc. I don't have a cure, but if you find one, I'll sign up too !

Hotblack Desiato

iwb wrote:

With the bigger kids, it won't pull them up the hill but it goes too fast downhill.

Nothing you can do about gravity! If the hill is steep enough it will gain speed downhill, power restrictor or not.
Only let them ride it on the flat if this is a problem.

padolicious

it probobly wont make it up the hill because the person on it is too big.
i know wat the info says on the quad but really 12 is too big for an 80!!
soryy if i sound like a bit of an ass hole!!!!!

Oryx

padolicious wrote:

it probobly wont make it up the hill because the person on it is too big.
i know wat the info says on the quad but really 12 is too big for an 80!!
soryy if i sound like a bit of an ass hole!!!!!

As long as they are not cramped on it, I wouldnt say so, it depends on the child. Ive seen some younger kids well able for an 80, and some 12yo's who are nervous on it. Rule of thumb re: size - the child should be big enough to sit on the quad, and stand up off the seat with feet on the footpegs. Other than that, parents/guardians, use your common sense.

galwaytt

it's good to watch them getting the skills.........it'd remind you of when you first sat on a bike/in a car, and how big and powerful anything with an engine was...........besides, waiting 'til they're 16/17/18 is just plain wrong to develop the co-ordination skills, imho. They're learnt better, younger.

And how do you know they're growing up?...........when you hear them keeping the throttle on the stop, rather than backing off at the turn at the end of the field............:D

iwb

The 80cc machine with unrestricted throttle can pull me up the hill no problem. The solution is to limit the speed for sure. I will keep on looking for something and if it doesn't exist, I may try to build something myself. It would just monitor shaft speed and cut the spark if it goes above a threshold.
Thanks for all the comments.