Are heavy bikes bad?

[Rockburner]

Heavy bikes are just different, they can still be a load of fun when ridden the right way.

[ZRX61]

I'll readily admit I have a thing about lightness,but I acknowledge the point being made.

My old ZZR11 was a heavy old bus,but it was a good road bike,because it was less flighty over bumps and rough surfaces,plus a longish wheelbase helped with stability. Easier work than a sportsbike when pushing on. My ZX10R was probably one of the lightest and close power/weight ratio ever and it was a real handful on the road at times.

That's why my ZRX11 is a keeper, engine was stuffed full of ZZR parts while it was still under warranty, quick port job & now it's basically the same hp as a ZZR but 100lb lighter. Scares the piss out of me sometimes.

[demographic]

In general I prefer light bikes but the feel of the suspension can be greatly affected by the ratio of sprung to unsprung weight.
Having heavy wheels on a heavy bike isn't so much of an issue because the suspension springs need to be pretty strong in the first place to achieve the right sag and that gives it the rebound speed it also needs.
With a lighter bike that has heavy wheels you should be able to use softer springs to have a plusher feel to the suspension but for the fact you still need strong springs to get the heavy wheel to rebound right on a bumpy road so it feels harsh.

Plus on a lighter bike you maybe have higher expectations of the bike and want it to hoss on a bit more.

If you have a light bike with light wheels you can have faster acceleration, deceleration, turning and still have softish springs because they don't need to be so strong to get the wheel rebound speed right for that stutter bumpy lane you know and love.

I think my GSXR is something like 195 kilos (dry weight which is a fairly bollocks measurement cosbthey don't run well without oil and fluids) and my KX was a hundred kilos before I added some road lights different wheels and legal stuff.
Both reasonably light considering I guess and I've never ridden a really heavy bike, mostly cos neither me nor any of my mates have bought one so theres not so much opportunity.

There's quite a bit about this in John Robinsons Chassis Tuning book with the maths and diagrams to explain it better but I've not read it for 20 odd years and forgotten most of it.

[Scotsrich]

My last 2 bikes have been heavy (ZZR and Sprint)

Fine on the move but a pig to get in and out the shed. Plus if you know they’re going over there’s not a lot you can do to stop them.

Obviously you can’t beat a smaller lighter bike on a twisty road but a well handled lump can shift as well.

[v8-powered]

My Trumpet ST1050 feels a weighty bugger when trying to move it.
I'm sure it's not the heaviest bike I've owned but when I have to push it out of the garage backwards and up a slope daily, it feels like a bloody bus. Rather it shed a few kilos......

[Mr. Dazzle]

All my most recent bikes have easily been 210kg plus. When my mum visited on her CB500 I put it in the garage and was expecting my usual level of resistance...I practically threw it in!

I think size, shape and height are as important to how a bike feels when pushing it around. The Bonnie isn't that light - I think it's about 175kg - but 'cause its really low and narrow (if I 'sit' on it with both feet flat on the floor I can get daylight under my bum) it is very easy to move around. I was actually surprised how heavy it is when I looked it up.

[Yorick]

My Trumpet ST1050 feels a weighty bugger when trying to move it.
I'm sure it's not the heaviest bike I've owned but when I have to push it out of the garage backwards and up a slope daily, it feels like a bloody bus. Rather it shed a few kilos......

Why don't you freewheel down backwards?

[demographic]

All my most recent bikes have easily been 210kg plus. When my mum visited on her CB500 I put it in the garage and was expecting my usual level of resistance...I practically threw it in!

I think size, shape and height are as important to how a bike feels when pushing it around. The Bonnie isn't that light - I think it's about 175kg - but 'cause its really low and narrow (if I 'sit' on it with both feet flat on the floor I can get daylight under my bum) it is very easy to move around. I was actually surprised how heavy it is when I looked it up.

Valid point, my KX isn't the easiest bike to push around despite being a huge amount lighter than most road bikes, but even with road wheels its still pretty high to the bars and can be hard to get my full force behind it pushing into a van.
On the move it's fine though, well if anything a bit flappy at speed and can be provoked into a slight tankslapper but its diminishing amplitude one thats kind of self cancelling after one concerned heartbeat.
The front wheel coming back into contact after a miss throttled mid corner bump kind of situation.

[The Spin Doctor]

I'm all for Colin Chapman - "simplify, then add lightness".

No matter how 'light and flickable' a heavy bike might FEEL, and no matter how powerful the motor to make it accelerate, you're having to work to make it change direction via the bars, and that means the tyres are having to deal with greater forces as you make it change direction. The same applies to acceleration and braking.

And as soon as you slow down, the mass starts to become a balance issue. At that point, the lower the combined Centre of Mass, the easier the bike is to handle. BMW knew that with their opposed twins, the NC series are designed to keep mass low down, and Yamaha didn't do a bad job either, with the FZ750's low 45 degree block and the fuel tank that sat just over the gearbox. That bike was a doddle to ride at walking pace compared with my WN 750 Gixxer with a conventional upright engine and a wide, shallow fuel tank strapped as high up as it would go. The first time I rode the GSX-R, I noticed it rocked from side to side at a standstill. It took me a couple of days to work out why - it was the fuel in a half-empty tank sloshing from side to side.

It's funny how often people rave about the ST1300. In my opinion, it was one of the nastier bikes I've ridden. Too heavy and top heavy with it, all in pursuit of a top speed and rate of acceleration no-one ever uses.

There's no reason a light bike can't have decent suspension. My brother's WR250 is lovely on a bumpy surface.

[Gregor]

I think my K100LT weighs in at 290kg, it certainly feels more stable at speed than any other bike I’ve owned including my old FJ1200.

Having the engine laid horizontally keeps a lot of the weight low down and I read somewhere the fairing was designed to create downforce at speed.

It's a heavy old lump to move around in the garage though.

I took the fairing off last year and it wasn’t nearly as nice to ride above 50 without the extra weight over the front, in fact it’d get a bit if a wobble on around 70 with the fork mounted screen and mirrors on the handlebars.

It’s the width that’s more of a pain than the weight, the mirrors don’t fold and that limits filtering and moving around it in the garage.

[v8-powered]

My Trumpet ST1050 feels a weighty bugger when trying to move it.
I'm sure it's not the heaviest bike I've owned but when I have to push it out of the garage backwards and up a slope daily, it feels like a bloody bus. Rather it shed a few kilos......

Why don't you freewheel down backwards?

Because generally the wifes car is on the drive, so I find it easier to ride in than freewheel back down the slope. Easier to control pushing backwards up the slope.

[Horse]

I read somewhere the fairing was designed to create downforce at speed.

BMW were doing that from the old air-cooled R100RS onwards. That fairing had winglets 30 years before the grand prix mob.

[Skub]

I read somewhere the fairing was designed to create downforce at speed.

BMW were doing that from the old air-cooled R100RS onwards. That fairing had winglets 30 years before the grand prix mob.

First proddy bike with a wind tunnel tested fairing,wasn't it?

[Horse]

Yup.

Although designer John Mockett once pointed out: "I could put my old mongrel dog in a wind tunnel and claim it had been 'tested'".

[Skub]

Yup.

Although designer John Mockett once pointed out: "I could put my old mongrel dog in a wind tunnel and claim it had been 'tested'".

Ha!

Something must have worked though,because the RS fairing gave great protection.

[mangocrazy]

Give me a light bike every time. The heaviest bike I own is an old VFR750 (conventional swingarm job) and that has a quoted dry weight of 203kg. In reality it's closer to 230kg and is just about at my limit for general pushing around and parking. The Falco is (allegedly) 195kg wet weight, although I think there's an element of porkies being told there. It's noticeably lighter than the VFR though.

And the KTM Duke is lightness personified (for a road bike). Under 150kg wet weight (and mine is around 5kg lighter than quoted due to jettisoning the cat). However because of its high bars it's more unwieldy to move around than its weight would suggest (for me, anyway). By comparison, my old 350LC (which is a similar weight) is a doddle, partly due to the difference in bar height but also because its weight is carried noticeably lower.

Which leads me to a pet hate - people justifying the lardiness of their chosen steed by saying 'but the weight disappears when it's on the move'. Of course it bloody does, but that's not much use when the bike's on its side due to a parking mishap, is it?

[demographic]

I read somewhere the fairing was designed to create downforce at speed.

BMW were doing that from the old air-cooled R100RS onwards. That fairing had winglets 30 years before the grand prix mob.

Downforce eh? Just an excuse for em not getting the front wheel up IMO.

[Horse]

I read somewhere the fairing was designed to create downforce at speed.

BMW were doing that from the old air-cooled R100RS onwards. That fairing had winglets 30 years before the grand prix mob.

Downforce eh? Just an excuse for em not getting the front wheel up IMO.

Actually, yes.

They claimed that UJMs suffered from reduced weight over the front at speed.

[demographic]

Actually, yes.

They claimed that UJMs suffered from reduced weight over the front at speed.

Ahh, the police bikes had heavy gear stored in the rear panniers with some bikes, weaved over the road a bit.
Can't remember if it was the BMWs or the Pan Ams or both.

[Bike Breaker]

Even a lightweight feels excessively heavy when you've protected it from harm by throwing yourself underneath it.
Trust me. I know these things.