Gear choice around town?

[Gizzit]

Hi there,
As I've newly returned to biking after a 35 year lay off ..... and Im on a bigger bike than I previously owned, I am a little unsure about how to treat my GSXF750 around town ... i.e. in a 50K zone. I have been trying to stay in the speed limit, and usually sitting in 4th gear, pulling a few revs, rather than getting into 6th and chancing labouring the motor.

Anyone got any ideas for or against gear choice with view to best economy and caring for the engine on a GSXF750 .... in 50K zones ?

Also what kind of gas mileage should I be getting around town on this bike with just normal riding .... i.e. not thrashing it .... just commuting to work and back?

Cheers,
Grant.

[merv]

If its geared about the same as my VFR at 50 you'll need 3rd, if you sneek over the limit when the plods are looking you might get into 4th. Anything higher in the gears than that you will be labouring the engine which is plainly not called for and don't shift into 6th until you're doing at least 90. Fuel economy if its as good as the Honda if you treat it nicely will be close to 20km/litre on easy running maybe as low as 16 around town.

[Gizzit]

If its geared about the same as my VFR at 50 you'll need 3rd, if you sneek over the limit when the plods are looking you might get into 4th. Anything higher in the gears than that you will be labouring the engine which is plainly not called for and don't shift into 6th until you're doing at least 90. Fuel economy if its as good as the Honda if you treat it nicely will be close to 20km/litre on easy running maybe as low as 16 around town.

Hi Merv,
Thanks for that. Do you know what kind of revs you are pulling in 3rd @ 50Kph ? I think I'm doing something around 3000 - 3500 in 4th ?

[merv]

About 3,500 in 3rd at 50. Just under 3,000 in 4th at 50 and I wouldn't normally let my engine run much under 4,000 so unless I'm doing more than 65 wouldn't have it in 4th. Your gear ratios could be a bit different of course.

[Black Bandit]

Labouring the engine? Wazzat?

What are the side affects? Why is it bad?

[xwhatsit]

Labouring the engine? Wazzat?

What are the side affects? Why is it bad?

Some people call it `lugging' the engine. It's just when the revs are too low for the engine to be very happy; I don't know about bigger bikes, but on my little 250 if I use too much throttle with too low revs, the engine vibrates a lot, doesn't produce smooth power, seems very loud -- occasionally there's even a knocking sound, which might be my barrel needing an bore and oversized piston, but you can tell it's stressing the engine. It should be very obvious when it occurs.

Somebody told me -- now this might be complete bollocks -- that when you open the throttle too much at low rpm under load, that because the piston is finding it hard to go up and down and there's little momentum, it puts a lot of side-to-side movement in the piston, pressing it against the piston walls. No idea if this is true or not, it sounds plausible, but I'm far from being experienced with the whirly bits that go around and around beneath my knees.

[Guided_monkey]

There's a further problem with labouring the engine. As the rpm's are low the oil pump isn't delivering at full pressure. The engine under load then causes the oil in the big end bearing's to be squeezed out and you get excessive wear.

Try a higher gear.

When riding at 'low' speeds I'm normally in 2nd/3rd.

[MotoGirl]

I often ride a 600 Bandit (similar sort of machine to your's) and I tend to sit in 3rd when travelling between 50 and 60kph.
On my own bike (twin) I'm generally in 2nd, maybe 3rd depending on how fast the traffic is flowing.

[Pwalo]

FWIW I'd concur with using third rather than fourth. Not so much too avoid 'lugging' the engine, but more to ensure that you have immediate acceleration on hand.

On the SV I'm usually in third with about 4K revs. I'm sure that the GSXF is a bit more forgiving if you're running lower revs.

[Chrislost]

so about 8000RPM in 2nd?
on my vfr thats just fastenogh for the plods to want to take your licence, and just enough revs so a twist of the wrist means they cant.

[TKDSKIP]

I'm only new so dont bite if I'm wrong but..... I would have thought that talk of "what gear do you ride in" is not relevant unless we all ride the same bike. RPM is better, as on many bikes anything less than 3500-4000 would be starting to labour the engine. The bonus of keeping the revs higher than this is that if you need to gas it to get out of the way you can.

Just my thoughts.

[Gizzit]

About 3,500 in 3rd at 50. Just under 3,000 in 4th at 50 and I wouldn't normally let my engine run much under 4,000 so unless I'm doing more than 65 wouldn't have it in 4th. Your gear ratios could be a bit different of course.

Yes Merv I think that is about right. I noticed going to work and back today that in 3rd at about 3500rpm I'm doing 50kmh, and about 3000rpm to do 50kmh in 4th. The bike sounds better probably in 3rd, so will use it that way. I don't want to stress the motor! I just thought I would be using a heap of petrol that way.Thanks for the input.
Cheers,
Grant.

[Gizzit]

I often ride a 600 Bandit (similar sort of machine to your's) and I tend to sit in 3rd when travelling between 50 and 60kph.
On my own bike (twin) I'm generally in 2nd, maybe 3rd depending on how fast the traffic is flowing.

Yes I think that our bikes (Bandit 600 / GSXF750) would run pretty much the same (very similar engine), and I think I will now run around town in 3rd and at about 3500rpm, it's doing 50kmh .... but yes ... just more about going with the flow of traffic .... and if some nice tin top wants to do 60 - 70 kmh in front of you .... well why not stick behind them for as far as you want !!
Cheers,
Grant.

[Gizzit]

There's a further problem with labouring the engine. As the rpm's are low the oil pump isn't delivering at full pressure. The engine under load then causes the oil in the big end bearing's to be squeezed out and you get excessive wear.

Try a higher gear.

When riding at 'low' speeds I'm normally in 2nd/3rd.

Yes I agree, and that was my concern about the revs at 50kmh. I will use 3rd gear from now on. It may suck through a bit more gas, but the engine will be better for it.
Cheers,
Grant.

[Gizzit]

I'm only new so dont bite if I'm wrong but..... I would have thought that talk of "what gear do you ride in" is not relevant unless we all ride the same bike. RPM is better, as on many bikes anything less than 3500-4000 would be starting to labour the engine. The bonus of keeping the revs higher than this is that if you need to gas it to get out of the way you can.

Just my thoughts.

Yes I agree with your comment regarding the bike, No "Bites" from me but yes ... thats why I stated what I was riding, so that anyone who has a GSXF750 (or a similar size/type of bike) may have an opinion about whats best for these 750's around town.

I came from riding a much smaller bike, .... and a long time ago .... so was just looking for general kind of views, from mainly other GSXF750 riders.

I agree with you about being in a lower gear to provide instant "get away" if you need to move quickly. It's nice having instant power!! 3500rpm in 3rd @ 50kmh works out pretty well for me. It feels a bit better to have it reving in that range, rather than 3000rpm in 4th, which can then more easily "chug", and I get instant grunt from that gear and rpm.
Cheers,
Grant.