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HTFU
27th July 2007, 22:25
I have noticed that the mighty GN is still for sale in mid 2007 and with the amount that will be hitting the second hand market I thought I would do a bit of a review of the bike for those looking at a first bike or commuter.

I bought the bike new in 2006 for $3300 and at the time nothing else was on the market as the yamaha scorpio had not hit the scene, I had just got my learners license and this was first experience with riding motorbikes. I did not know that they were now chinese made, but do not think that would have changed my decision to buy it as I had limited funds and wanted something new.

Riding setup.

With a low seat height and an upright position for small trips around town the bike was fine but as soon as I was on it for more than 20 minutes my back and ass would ache something savage. I thought this may have been something I would get used to but after 6 months it was still uncomfortable to ride. I fitted cruiser pegs to the bike in a similar position as the suzuki 250 marauder (crusier style with GN motor). This along with a small backrest I made using foam (and an upholster to cover it) made it a lot better but still not the best. Fitted some ventura straight bars ($40) and man what a difference. Because you are leaning forward the weight comes off the ass and no pain (even 2 hours on the bike without stopping presented no problems. I hardly use the cruiser pegs anymore because it is so much more comfortable.

I am 1.75cm tall and the bike is ok for me, you would not want to be much taller to be comfortable for longer trips though. You can fit a ventura rack system and bag to the back and take a pillion on short trips, but not too far.

Performance

The bike takes just over 10 sec to go from 0-100 so is not too far behind most standard 2.0 cars. It has a top speed of 130km/hr on the flat with no head wind and in a tuck. With the normal 41 tooth rear sprocket you will be in the red line of 8000rpm at this speed. I do a lot of open highway riding on the bike so fitted a 39 tooth sprocket when I replaced the second chain today. It had no real effect on top end speed (5km/hr at the most) as the GN is low powered, but it is revving lower (not sure what as rev counter is not working, broken cable). The 39 tooth gives 4th gear more pulling power around 90km/hr and will take you to 110km/hr which is great for passing. The original setup is not ideal as you hit the redline at 100k in 4h and have no power in 5th, which at 100km is an overdrive (6000rpm). Original setup would be fine for around the city.

I travel at 100-110km/hr on the open road and this in the normal riding position is full throttle most of the time (120 if you have a tail wind or if you tuck down you can get up to the 130k), I dont recommend trying to pass at 110km/hr unless you have a tail wind and a long straight as you run the risk of getting stuck on the outside. At this speed you will get 175-185 km from the 8 litre tank before reserve (another 1.5 litres). If you sit on 90-100km you will get 200+ km ) This bike is actually cheaper to run around town than it is on the open road trying to maintain highway speeds. Best economy I got was 280km from the 8 litres using it in Auckland for a week, although I once travelled at 70km an hour running it in on some flat back roads and got 330km from the 8 litres.

Wind and hills have a big effect on your speed on the open road as a result of its simple engine and low power. I travel 60km one way commuting on the bike and into the wind on the flats it will maintain 100km/hr but only just, sometimes you have to tuck down if it is a really strong wind. On the hills you have to hit them at 110 and then as the speed drops to 100 use 4th. This is where changing the sprocket will help, as you wont be ringing the bike out when you change down and it will sit between 90-100km on most hills on the main highways. The GN would be awesome with just a few more kilowatts to help with passing.

The original tyres are a death trap and I mean that. Replace them if you are going to use this bike on the highway in winter conditions. $80 for a front tyre and $120 for a rear will get you some better rubber (most good brands do a GN size tyre) I actually run Duro dual purpose tyres on the rear and a Yokohama semi knobbly on the front and have never had a problem like I did with the originals (both front and rear have slid out on minor lean angles and no braking). The bike is very easy to ride, with the dual purpose tyres I have used it on every road surface. You can lean it over and grind the pegs in the dry if you feel the need and it rides well on gravel roads with the straight bars and semi upright position. The disc on the front works well enough so braking is not really a problem.

Problems and maintenance

I recommend changing the oil and filter and cleaning the air filter every 4000 km on these bikes as they only hold a small amount of oil (1.3L) and need every little bit of power they have. The chain should be lubed everyweek as this is a area of concern on the GN and especially if you do long rides like myself. You seem to need to adjust the chain alot (not sure if this is normal) but this is simple to do with the bike on its centre stand. I had the valve clearance and spark plug done every 10000km. I replaced the original chain at 8000km with a standard heavy duty type ($50) these use a joining link and I got 12000km out of it. These chains works fine even thought the manual says use a continuous type chain. The front sprocket is still original and the rear lasted 20000km on the two chains.

There is no doubt that the chinese bikes are of a poorer build quality but I do not know how this relates to the motor as yet, which has been fine. Electrical system is a constant problem with blown bulbs as is the speedo and rev counter which have all stopped working. The muffler and chrome have surface rust. Everything else has been fine.

General recommendations

The GN is a great bike for a mid-sized newbie rider as I was. With the simple modifications to the setup of the bike you can create a comfortable, cheap go anywhere bike to meet a range of riding needs. One of the $7000 sport v-twins from Kawazaki and Hyosung will set you back twice the money but may give you the extra speed and passing power you need, so look there. But if you don't have the coin, are new to riding and are not in a hurry, then the Chinese GN is still a good bike for less than $3500. It may also be a safer choice in many ways than buying a used higher performance bike for some new riders and also considering the risks second hand bikes come with.

The similar priced Yamaha Scorpio looks to be a higher quality build and is also worth a look. Performance wise it may have a bit more go and therefore be better on the highway. A low milage GN for $2000-$2500 second hand would be a good choice for someone with thoughts of a bigger bike in the future.

Steam
27th July 2007, 22:31
Great review dude. I fully agree.

irishlad
28th July 2007, 17:38
Great review. Would be interested in seeing some pics of the modifications.

Das Bruce
30th July 2007, 14:59
I bought a GZ in auckland and rode it down to dunedin over 3 days, the engine really does lack power at about the 80-100k range with the standard sprocket.

Good review.

Chill
31st July 2007, 13:19
Very good review.

Interested in:
'Fitted some ventura straight bars ($40)'

Where did you get them? Did you fit them yourself? Total cost?
Might be an idea for my GN

HTFU
31st July 2007, 16:47
Where did you get them? Did you fit them yourself? Total cost?
I purchased them at road and sport in Hamilton. They had two models a ventura 3 and ventura 5 both $40. The 3 was flatter so I went for the 5 which had a small rise. They are easy to fit yourself you just have to loosen off your stem bolts first, so that you have enough cable movement to slide controls off, and then the screws under your controls will allow them to slide off. Left hand grip will slide off with airgun and right is part of the control. Be careful with the screws as they can strip out the plastic thread easily, so you need to do them up evenly. The new bars did not have holes in them for the controls to slot into (you need these to stop the controls (especially the throttle) from moving when you twist the grips. I choose to grind the plastic knob off because I couldn't work out where I wanted the bars so needed to move the controls around which you can not do once you drill the bar. I then fitted allen key bolts with a larger diameter bolt, so I could crank them up to stop them moving, you wont need to if you drill the bar. They totally change the bike and its a shame they are not standard.

I also fitted new mirrors because the bars are lower than the originals so the old mirrors don't go out wide enough ($20 from wrecker in Ngauruwahia), indicators $50 new, cruiser pegs $25 new (plus alloy from wrecker). Seat bag $50 from upholster , rear rack $150 ventura, rack bag $75 Dans Bags Otorohanga, Tank bag $50 new.

delusionz
31st July 2007, 17:03
There is no doubt that the chinese bikes are of a poorer build quality but I do not know how this relates to the motor as yet, which has been fine. Electrical system is a constant problem with blown bulbs as is the speedo and rev counter which have all stopped working. The muffler and chrome have surface rust. Everything else has been fine.

Sounds exactly like what my last bike did, and then one day the spark went too. Except lucky for you, your bike is branded Suzuki so motorcycle shops will be inclined to help you with it. No such luck for my old Chinese pile of shit (http://www.nzecobikes.co.nz/cruiserss.html), Hence I got the Kawasaki.

MaxCannon
31st July 2007, 22:34
How did you find a piece of road long enough to make it up to 130kph

Mine hits nearly 8000 rpm at 110 and it's not got any more to give.
Maybe it could 120 down a steep enough hill

For fuel economy those figures sound pretty good.
I get 25km per litre week in an week out.
Mostly round town riding but my commute does have a 6km motorway section that is normally full throttle.

HTFU
1st August 2007, 00:43
How did you find a piece of road long enough to make it up to 130kph

Mine hits nearly 8000 rpm at 110 and it's not got any more to give.
Maybe it could 120 down a steep enough hill

My GN has always been able to do 130 on the flat from new but you have to tuck down slightly, does not take long to get there and is very wind dependent. Now with the new 39 tooth sprocket it will do 135 in a tuck on the flat.

Even with the old 41 tooth sprocket it would only rev at 7000 rpm at 110 and 120 was just under the redline. You may have a 42 or 43 tooth sprocket on your bike for it to be revving as it is. Also I weigh 75-80 kg, so if you are festively plump then that may be a factor also. With the old sprocket at 100 km it was just on 6000 rpm, not sure what it does now as rev counter is not working.

I once went up the Bombay hills South to North at 120 all the way in 5th, had a tail wind and was following traffic so that helped. But somedays 110 is all it will give on the flats in my normal riding position going into a slight headwind. With the same wind behind me sitting up it will do 120 and then the 130-135 if I tuck.

Strong winds will drop it to 90 if I am sitting up going straight into the wind and so I have to tuck down to get 100 out of it, but this is only on rare occasions where I am on a stretch of road going directly into a gale, and now with the 39 tooth and lower revs I can just chuck it into 4th to get it back up to 100 without the need to tuck down.

In general I find my GN is sweet for highway cruising at 100-120 on still days with either a tailwind or a headwind but it can be a bit restricted going into the wind during a gale.

MaxCannon
3rd August 2007, 14:52
Big + 1 on the tyres too

Only real hardstop moment I've had was on the standard tyres. They were hopeless in the wet.

I have a set of Pirelli city demons now and the bike is much better behaved.