does a gpz500 rattle at 70mph in the way an old er5 does ?

[colin1]

last bike lesson i took the now familiar P reg er5 on a national speed limit dual carriageway and was surprised when it got quite rattley at 70mph.

I found this a bit offputting as at lower speeds it solid as a rock.

One of the bikes I am thinking about getting is a gpz500 but as I'd ride at 80mph sometimes, i want something that doesnt start shaking at that speed.

I'm gonna test ride different bikes, but if its a common thing i'm not sure i will bother with the gpz500.
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[Sheepy1209]

Not sure what you mean by rattly - at that sort of speed my GPZ500 feels a bit buzzy, I wouldn't like to cover long distances on it.

But - the whole experience of riding a bike even at sixty is initially quite alarming, especially on a naked bike like the er-5. First time I took my GPZ on the motorway I wanted to jump off, it felt that unsafe.

Personally if I'm going any distance on this bike I'd take the A-roads - much more fun, it's in its element mixing it with traffic. Also, the standard mirrors are totally inadequate for motorway riding.

[colin1]

my rs125 is fine at 80mph just a bit skittish. this is why i was surprised that the er5 which feels more solid at lower speeds is more rattley and shakey at 70mph

it could be cos my rs125 is faired and the er5 isnt so the gpz500 could solve this
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[0ddball]

Mine doesn't feel particularly rattley but at about 80mph you notice a big increase in wind resistance. It just sort of steps from next to nothing at 75 to a full on huricane at 80.

Despite this is is still quite stable and feels safe enough.
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[stinkwheel]

Depends on how you are riding it. A GPZ500s will be sat in a big fat flat-spot at 70mph in top and making no power at all. This is good for fuel economy but opening the throttle doesn't do much other than make it bog and clatter. For decent acceleration at that kind of speed you would need to change down two to three gears and hang on to your hat. The power in top gear only really kicks-in at about 100mph (8k revs).

The way to ride it is to treat top gear as an 'overdrive' to cruise along at a steady pace using very little fuel. If you want to accelerate, change down.

Ragging the arse off a 500 twin takes a bit of getting used to, remember, this bike will be doing 60mph in second gear if you take it up to the red-line.
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[colin1]

it didnt feel as if it had run out of power, but i think it could be a choice of gear I think like stink said. having said that, it wasnt when i was acclerating but when i was cruising
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[Kickstart]

Hi

Do you mean the engine felt rattly? Not really noticed anything like that with the GPZ500, although they can get rattly with age.

However if you mean the bike felt unstable then the problem could be the way you are gripping the bars. Holding on tight to counteract the wind tends to provoke a weave on any bike. Try relaxing your grip a little and leaning forwards into the wind instead.

All the best

Keith
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[colin1]

it didnt feel like the the engine, it felt more like the whole bike was juddering, the frame bars etc

im not talking about high frequency vibration and im not talking about engine judder when you are loading the engine at low revs in too high a gear (althought it might have been that but i dont think so)

the bike wasnt weaving. it wasnt jittery it was more juddery. big amplitude low vibrations

im having another lesson next week so i will post here with a better description if it happens again

the rev counter doesnt work
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[Rik]

sounds like the wheel alignment may be out????


rik

[colin1]

if the wheel alignment is out, are you talking about the back wheel ?
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[Kickstart]

Hi

They are a bit juddery like that. Down side of a parallel twin set up like that. You get used to it.

All the best

Keith
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