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Hi all from NZ

When riding in urban areas, when in no rush, what is the lowest rpm recommended? I.e. is 3000 rpm too low when crusing in town in 5th or 6th?

Similarly what is the recommmended rpm when changing gear? Again when in no rush. Ive come off a Ninja 250, so not familiar with the GSX650F personality, but at 4000 it changes to a smooooooth sound. I read somewhere that 4000 to 8000 is its nice operating area, so I am wondering if keeping the rpm at 4000 lowest is best? For economical city riding I am wondering what the lowest rpm is that wont add any stress when cruising along. 3000 too low?

Cheers
Tony
Christchurch, New Zealand (4000 aftershocks later)

For me, 3000 rpm is the low. 5th and 6th are too low for around town cruising. The bike won't bog down, and it will eventually build speed in those gears, but it won't pull with any guts.



If I'm in no rush, I'll probably shift when the revs get between 4200 and 4500. If I'm getting on it, I shift between 6000 and 7000.



My bike does just fine with revs down to about 3000, so I don't think that 3000 is too low. I rarely have any need to get the revs up near 8000. If I make a quick blast up to speed, I may, but it's not typical for me. I tend to keep the revs between 3000 and 6000, but I don't really thrash the bike at all, obviously.

And this is all keeping in mind that I don't usually even look at the tach when I'm riding, particularly in a congested area. I only occasionally glance at it. The power band on this bike is so wide that I really don't have a need to watch the tach, or to consciously make an effort to keeep the revs up.

It is a pretty subjective question so you will get many varying responses, but here is my take:

The general rule is that the lower the gear, the less stress the engine is under at lower RPMs. In other words, the bike has no problem trundling along at 2000 RPM in first gear, but in sixth that would be lugging the engine badly.

Apart from slow manouvering (which I do in 1st-3rd gear), I try to keep the bike between 4000-5000 RPM when cruising. The engine just seems happy there. After riding it for a while you will (hopefully) get to know how the bike feels when it is "happy".

Also bear in mind that it is an inline four. Dividing the engine capacity by four results in 4 small cylinders (162 cc) and pistons, and the smaller the pistons, the happier they are to move quickly. Larger V Twins (e.g. a 1300 cc cruiser) will have much larger pistons (650 cc each cylinder/piston), resulting in more mass per piston making the engine reluctant to spin quickly. So long story short, the 650f's engine may be a little more rev-happy than other bikes you may have ridden, depending on your riding history. 5000 RPM is certainly not stressing the 650F at all.

As for when to change gear, if you are going the maximum bang for your buck you should ideally be changing based on maximising your usage of the torque provided by the engine. Unlike a pure sports bike the 650F is tuned more for "mid-range usability" so taking it to the red line is unlikely to be the most effective gear changing strategy. Personally, if I am feeling naughty then I will change up at about 8000 RPM, or sometimes 10,000 RPM in second gear (thats just so much fun ). But in normal riding I will change up/down so that the current gear remains around 4000-5000 RPM.

Having just moved up from a Ninja 250 you should be accustomed to high RPM ride the 650F with a few less RPM and you won’t go far wrong.
Steve

2nd or 3rd gear around town. Mostly 2nd gear when in congested city traffic, and 3rd when near 35 mph. I never paid attention to the rpms. I shifted according to what I wanted the bike to be able to do in the conditions I was in. Why bother even looking at the rpms? Heck, in city traffic, why bother looking at the speedometer? There's little need for that visual information, unless riding in a school zone at 20 mph.

I thought that too low rpm/high gear damages the crankcase bearings?

That is also my impression.

I found this at http://hubpages.com/hub/Guide-To-Four-Stroke-Motorcycle-Engines-Part-5

....and he's a mechanic with 30 years worth of qualifications.

I use 3/4th gear around town. 50km/h speed limit and I go up to 65km/h on the speedo. When the engine is cold I shift at around 3500rpm untill the oil goes above 40 degrees C, then untill 60 degrees C I dont rev it higher dan 5-6k rpm and above 80C I use the entire rev range

I believe the engine operates at its best effeciency around 4-5k rpm. But I average around 18.5km on 1 liter fuel. Full throttle highway (top speed riding) results in 16km on1. And cruising around going 70-90km/h (3500-4500rpm) results in 20-22km on 1 liter fuel.

[quote="tdale"]Hi all from NZ


Hi and welcome Tony

Have you actually tried doing this though? It sounds like pretty bad advice, though if you respect his opinion thats all that matters. I could be wrong, I'll give it a go tonight...

Well, I rode around in top gear, down to about 40km/h which was below 3000 rpm. The bike didnt seem to complain, which rather surprised me. It was pretty gutless and not much fun, but it was certainly do-able. I wonder what effect it would have on fuel consumption to ride around like that all the time...

Hello and welcome tdale.

Around town 1.2.3rd gear ,you need power on tap ,to get away from the idiots.
You can talk about if it can do it or will it damage the bike .....
But the main goal in riding is to make it to were you want to go, and in 3rd gear cruising around town ,it will get you out of trouble quicker then in 6th.

Thank you all for your feedback and useful commentary. All useful. I love this bike, its got power, easy to ride and comfortable, only have done 670km so far. Based upon the "feel" and all of your words, I have evolved into keeping it over 3000rpm. If I am going at a steady, able speed, whether that be 40kph or 55kph etc I am happy with it at 3000rpm. I will accelerate gently from there but if I wish more get up and go, its 3500 to 4000 time. With more peppy riding I will off course use more rpm. My concern was using too few rpm, but also keen to not waste engine rpm/fuel at lower steady speed when commuting.

Off topic, from new (well 2.4km) I found the gears clunky when changing. That has gone away, partly I guess me getting used to it, but the gears or gear changer mechanism will wear in as I have read. Gas mileage was 60 mpg (Imperial) which wasnt bad and the gas gauge is accurate, it went to the last 1.5 litre flicker and when I filled it then it took 17.5 litres, exactly right.

Thank you all again and I will browse the other threads for info and to join in and put some ideas back

Cheers
Tony
Christchurch.

Dont know if any of you realise we have had a 7.1 earthquake in Sept 4th. Been 25 aftershocks over 4.8 and about 4100 since Sept 4th. Now, we get only 1 or 2, or less per day but we are getting sharp 4's every few weeks. Our down under mates across the ditch (Tasman Sea) are having there faor share of natures torment, prayers to you all.

Cheers again
Tony