Reving an engine

[katana]

Hello all,

Well no specifically a bike question but more of a mechanical question.

If I run and engine at maximum revs, the revs that it gives maximum bhp, will I damage the engine? This of course with the bike in gear and traveling down alonf a road.

Is there a difference between 2 and 4 stroke machines?

Just really to settle my mind more than anything else

[Scotsman37]

You'll probably end up seeing engine oil spewing all over the road because I've seen it happen if you keep it for prolong periods of time. Remember engine oil does evaporate due to the high temperatures at while running high speeds and so you could end up with a lump of metal either that the piston,etc, will try to shoot out of the bike if you don't keep an eye on the engine oil level and you'll no doubt have to replace the engine oil more often.

That's if you do it a lot and that's if you want to experiment with your bike at high revs to see what it's capable of doing then you have to be able to afford to lose the engine and/or buy a replacement parts as and when they quickly ware out !

Professional stunt riders have their bikes regularly stripped by a mechanic and have them rebuild it as they can afford this due to being sponsored by various companies. Professional race bikes have most of their moving parts replaced after 3 days of racing due to the high ware of race day parts.

[DukeRed]

I thought that high reving bikes like being revved to just short of the redline. I heard it was bad to drive with low revs if it was a high rev bike.

Gets rid of caked coke as well.

I redlined it from Scotland to London and the bike was fine and still is.
____________________
Enjoy Life There's Plenty of Time to be Dead
https://www.janoner.com

[BlueNinja]

lots of rev's = lots of heat. lots of heat = more engine wear, more engine wear = shorter engine life, + degrading performance of all engine parts and output performance.

Dont do it. When an engine is warm enough, its ok to reach redline now and then, but never ever rev a cold engine, or rev and engine too much while it is stationary as it will get inadequate cooling.

To remove engine junk, like the carbon build up, either have it re-built, or flushed. But never resort to engine revving for this!
____________________
Big Kawasaki ZXR 400 project here:
https://www.theundertaking.com/index.php?showtopic=483

[G]

I have ridden various bikes with the revs held at peak for sustained periods. Had no significant ill effects from /this/.

The revs it gives maximum bhp will usually not be the redline, sometimes qutie a way under.

It is going to wear the engine more doing this, so you're advised to cheack and replace the oil more often. People with track bikes will usually replace the oil every two trackdays, to keep everything fresh. On some production two stroke race bikes people will hold the bike well into the redline for 2/3rds of long straights. The engine revs will idealy stay high for the majority of time on track, if the bike is ridden well.


The way I see it, If I'm riding a bike for fun, there's no point pussy-footing around just to save a bit of money... I could have gone for a basic commuter bike if I was going to do that.

[Kickstart]

Hi

Generally I would say you are safe going to the red line regularly, and into the red occasionally. Just make sure it is up to operating temperature.

Revving the engine at high revs will increase wear, but unlikely to be a real concern in real life if you only do it once the engine is warm and are changing the oil regularly.

Yes, lugging an engine at low revs is now good for them either. However most people would change down rather than putting up with it shuddering from that.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Finglonga]

Also most 'new' bikes(4 strokes) have rev limiters on so that you can't over rev them. Mine cuts in at about 500rpm into the red line but peak power and torque is 2K below that.
____________________
Andy Sez....
F.Y.Y.F.F.

[bish777]

dipping into the red now and again wont hurt, running at higher rpms wont really either on most motorbikes, but give the ppor thing a break when just travelling about and short shift to a high gear and run at low RPMs

If you have an older bike be careful as many will rev till destruction (GPz 305 for example)

[katana]

Don't worry,

I know that engine are to be used when warm. Just a disscussion I was having on visordown and I have a rudementry knowledge of engine and all my friends say once warm a road engine after running in is fine to sit at the maximum bhp revs without any problems.

Understood that the engine is serviced properly.

Some on there were saying that it is bad and will blow the engine up if I do it a lot and never had any problems.

[pipnet11]

Max power is not always max revs. Eg. Suzuki GS125 has a max power of 14.5bhp at 7,000-ish revs, the red-line is 9,500. Its max speed was well within the limit, 65mph at 8,500rpm. It would sit at 60 mph, 8,000rpm for as long as you wanted, as long as you didnt encounter a hill or headwind
____________________
I love the girls that do, I hate the girls that dont, I hate the girls who say they will and then they say they wont, but the girl I like most of all and I think youll say Im right, is the girl who says she never has but looks as though she might. - Max Bygraves