Couple more questions on GS500

[Beelzeboss]

Hi,

First post here, and let me just say that I am not buying a GS500 to use on the road, but if I was wanting a bike then it would be one of my first choices. I am buying one which is a statutory write off (can never be registered again) to use the engine in a small off-road buggy.
My main question concerns the fact that the bike which I am considering may not have a key or the ignition barrel intact, the whole front end is mangled pretty badly. So, can I replace the ignition barrel and key with a toggle switch and starter button?  Or, will I have to buy a whole new computer for the bike which is matched to a new ignition barrel? (Some Honda bikes and possibly the GSXR range have this security feature, I think).
Also, since this buggy will be doing many powerslides I am thinking of putting in a rev limiter at about 9,000-9,500 RPM to stop the engine wearing too badly, or failing completely. If a friend drives the buggy I don't want them to blow up anything by just planting their right foot all the time. Can anyone think of a reason why this is a bad idea?
Lastly, does anybody know where I could get a workshop manual for free? Or at least the wiring diagram? I am on a very tight budget for this buggy, otherwise I would buy the workshop manual.

Regards,
Andrew

*EDIT* It's an '06 engine with <10,000km on it if that helps

[fred]

Hi. Welcome. You can replace the ignition with a plan switch, no problem. There is no computer on the bike, so it doesn't really matter what you use.

You should avoid revving the engine over 10,000 rpm otherwise the valves will float and your engine will be toast. I don't know how you'd actually limit the revs though... I don't know of anyone here who's actually done it...

There is a copy of the official suzuki shop manual floating around on the net somewhere... You should be able to find it in PDF form with google... Also, if you're only looking for a wiring diagram, look on the wiki, I think there's one there tool.

The buggy sounds cool, you'll have to post pictures when you're done.

[bobthebiker]

To limit revs, I would simply set up a throttle stop of some manner.    its probably the most effective way, being 99% of the GS500 engine is mechanically controlled.   

I love the pick of destiny reference as a username btw.

[fred]

To limit revs, I would simply set up a throttle stop of some manner.    its probably the most effective way, being 99% of the GS500 engine is mechanically controlled.   

I love the pick of destiny reference as a username btw.

That won't work. Different throttle settings mean different RPMs under differing load conditions. Under no load at all you could probably redline the engine at half throttle while under a huge load you might not be able to redline it at full throttle. You have to do something more complicated than just a throttle stop, probably a lot more complicated. I'd just mount the tach off the bike and make it clear to whoever is driving that if they redline the thing they're responsible for helping your rebuild it.

[Beelzeboss]

Thanks for the replies.
I'd like to try for an electronic limiter of some sort. Won't limiting throttle position lower the power output throughout the entire rev range? There used to be a kit you could buy from Jaycar (like radio shack in Australia) that could add a rev limiter, but I guess with most new cars already having rev limiters the kit became unpopular. I will probably ask my friend (bit of an electronics guru) to help work out some kind of limiter.
Could I just wire up the limiter to the kill switch? So above the limit it would be like holding the kill switch. I imagine this would work fine, but my experience with bikes is limited to a Honda 50, and later a 1995 or so Suzuki DS-80. That was fun.

Regards,
Andrew

Good to know someone has seen/heard of Pick Of Destiny  

*EDIT* just saw your reply Fred. I thought a throttle stop would do that.

[fred]

Electronics are the way to go. Come to think of it, I think the '06 engine you have has an electronic tach. The older bikes (like mine) have a mechanical tach, but the newer ones are electronic. If you could interpret that signal correctly you could do exactly what you described. If you're lucky, the electronic tach is basically a big volt meter so you could cook up a circuit that just looked for the tach line voltage to go over a certain value then cut the ignition....

[bobthebiker]

Thanks for the replies.
I'd like to try for an electronic limiter of some sort. Won't limiting throttle position lower the power output throughout the entire rev range?

Good to know someone has seen/heard of Pick Of Destiny  

I think if you've got a friend or two that is good with computers you can design a rev limiter to work with your system, but I'm not certain.     

I loved the POD movie it was pretty good

[Beelzeboss]

Alright, I'll try to work out some kind of electronic limiter.

Also, for anyone interested, I found this site which has MANY bikes workshop manuals (including the GS500) http://www.manualz.info/
Enjoy!

Andrew

[Beelzeboss]

I have a few more questions about the GS500. What is the theoretical top speed? i.e if the engine was revving to maximum in top gear, how fast would you be going?

How many teeth are on the engine sprocket, and how many are on the rear sprocket?

Lastly, what is the overall outside diameter of the rear tyre?


Trying to work out what sprockets to use on the buggy to get a reasonable top speed (110kph), as I want to maximise acceleration.

Regards,
Andrew

[ohgood]

I have a few more questions about the GS500. What is the theoretical top speed? i.e if the engine was revving to maximum in top gear, how fast would you be going?

How many teeth are on the engine sprocket, and how many are on the rear sprocket?

Lastly, what is the overall outside diameter of the rear tyre?


Trying to work out what sprockets to use on the buggy to get a reasonable top speed (110kph), as I want to maximise acceleration.

Regards,
Andrew

theoretical top speed is like 129 or 139 or some ridiculous number. there is s a gearing calculator somewhere on the forum, search function will find it.

stock front = 16t, stock rear 39t

circumference of the rear tire ? hmm, i suppose you could calculate it somehow, 130/70/17 is the stock size iirc.

got any pictures of your buggy ? any engine with 20+ hp will make for allot of fun riding, i remember when 4-wheelers were 'big' if they had >300cc's

wear your gear, and pad the inside of the cage

[Beelzeboss]

Thanks very much ohgood. Very good advice with the frame padding, it really hurts to even lightly bang your knees or elbows on the frame. The buggy is currently still in construction so no pictures as yet, but you can see what it will (should) look like when finished here: http://edge.au.com/buggies_sidewinder.htm. I've finished the front suspension, done about half the rear suspension and about half the frame. Those are the 3 main fabrications so I'm well on the way to finishing.
I will take some pictures tomorrow to show where I am so far.

I was originally going to get an 08 Hyosung GT-650 engine with only 4,000 but was out bit at the auction by $100. That would have been 79hp or something stupid, but I think the 47hp of the GS500 will work just as well, and not brake things as quickly.


So, how much abuse can these engines take? Are they strong internally, or will I have to rebuild it at 20,000km? (It's at 9,500km)
From what I've read so far on this forum they are very reliable, but the engine will be under A LOT more stress in the buggy than in the bike.

[ohgood]

1) So, how much abuse can these engines take? Are they strong internally, or will I have to rebuild it at 20,000km? (It's at 9,500km)
2) From what I've read so far on this forum they are very reliable, but the engine will be under A LOT more stress in the buggy than in the bike.

1) plenty. keep her full of oil, and change it regularly. before you start thrashing her hard, check for GOATS and STALWARTS syndromes and you'll be fine. (forum searches will turn up what i'm talking about)

no, you won't have to rebuild for a while. 50,000-80,000 miles seems to be the norm with proper oil changes.

[bobthebiker]

I was originally going to get an 08 Hyosung GT-650 engine with only 4,000 but was out bit at the auction by $100. That would have been 79hp or something stupid, but I think the 47hp of the GS500 will work just as well, and not brake things as quickly.

Actually, the hyojunk motor would have been more like 0 hp since they die easy and frequently. poorly built steaming piles of fail.    right around 12k miles they ALWAYS fail.  they're not even actually suzuki motors, just cheapo knockoffs that LOOK like a suzuki SV motor.    and good luck finding parts or anyone who will repair those pieces of garbage.  (yes I HATE hyosungs)

Like ohgood said, just check for goats and starwalts,  syndromes, keep the oil changed, and your valves adjusted appropriately, and you'll have a dependable little motor.  I trust the GS motor a lot, despite its little flaws, its a great motor for a cart, or a bike. 

[gsJack]

Theoretical top speed in 6th gear is 140 mph.

[qwertydude]

It wouldn't be too difficult to fabricate a rev limiter, all you need to do is cut power from the ignition coils when you over rev. I'm sure you can find something on ebay to whip up that and a set of relays that will cut power to the coils.

[natedawg120]

It wouldn't be too difficult to fabricate a rev limiter, all you need to do is cut power from the ignition coils when you over rev. I'm sure you can find something on ebay to whip up that and a set of relays that will cut power to the coils.

Yeah that is what i was going to say, just modify the tach circuit to limit revs to under 10k - relay kicks on at whatever voltage that is and kills power to the coils momentarily.

[Beelzeboss]

That's probably what I'll end up doing with the limiter.

I saw a great idea on the internet which would work. Somebody game me an autometer monster tacho with shift light. You use the shift like as the trip for the rev limiter. Since you can adjust the shift light RPM setting on the fly you could also adjust the rev limiter. So if some idiot is driving you put the limiter down to 6,000 RPM like a car, and when I want to tear it up put it up to 9,500 or so.
However, since the coil fires when the magnetic flux inside it is removed, by cutting the power to the coil you can cause a spark to fire. The problem is that the spark could occur at the wrong time (half way through the compression stroke) and cause damage to the engine. Does anybody know where in the circuit would be best to cut power? I would have though the high tension side of the coil so there is NO possibility of a spark, but then you need a switch which can handle the thousands of volts.

[fred]

That is a cool idea. Why not just use the existing kill switch? That cuts the engine just fine and if you're really worried about it, just set the limiter to a bit below the red line. The GS engine is rated to 11500 RPM but doesn't really make that much power after about 10k, so you've got plenty of headroom to play with...