Topic: Engine knocks occasionally before failing to start.

[juntjoo]

dont be scared to ride around town in a lower gear to keep rpm high,dont lug these bikes at less than 2500 and try to keep the revs low,they shine at higher rpm and will be ready to gun it away from trouble if need be,they cruise at 4000,theyll sit at 5000/6000 all day even more,its the way they are.

I do keep em high. I learned to over time by necessity.

What is it about these engines that "like" higher revs? Or what would be an example of an engine that prefers lower rpms vs why exactly?

[dave500]

these have a short stroke "over square"cylinder where the bore is wider than the stroke,they need rpm to make torque(pulling power),an older design long stroke motor has the bore less than the stroke,this design makes more low rpm pull or torque but wont rev much,they are best left to lug and chug chug chug,old english bikes are an example,or harleys?

[dave500]

a lot goes into the design of engines,not just the bore and stroke but how long the con rod should be,its all very complex or we would all be doing it?

[Kevnz]

I bought my first bike, a 500\4 in 1973, had 8 or sohc\4s since then, and I have never, repeat, never had a charging issue with any of them. I generally ride with economy in mind, so , no higher revs than necessary, just ride normally. Never had a battery go flat on me. Am I just lucky?

[juntjoo]

these have a short stroke "over square"cylinder where the bore is wider than the stroke,they need rpm to make torque(pulling power),an older design long stroke motor has the bore less than the stroke,this design makes more low rpm pull or torque but wont rev much,they are best left to lug and chug chug chug,old english bikes are an example,or harleys?

Ah! Makes perfect sense! I got it. Now as I'm looking over specs that will mean something to me. I guess a dump truck should have  a lower bore to stroke ratio. Idk why. Am I wrong? If I were to reshape my legs for a sprint I'd want em shorter...  It after reaching top speed I'd want to stretch them back out. Inspector Gadget probably had this down

[dave500]

leverage vs speed?most engines these days are over square,its the percentage though.

[Kevnz]

Used to run Jags in the day. They were undersquare, 106mm stroke. Only revved to 5500, but had great torque down low and great for overtaking. No need to change down. IMO, torque is more relevant to road performance than power. It's all very well having heaps of horsepower, but if you have to be in the right gear to access it, often a passing opportunity is lost whereas with torque, just bury it. My boss had a 535 BMW which was a goer, but on a busy road, my 3.8 Mk2 Jag would eat it.

[juntjoo]

Used to run Jags in the day. They were undersquare, 106mm stroke. Only revved to 5500, but had great torque down low and great for overtaking. No need to change down. IMO, torque is more relevant to road performance than power. It's all very well having heaps of horsepower, but if you have to be in the right gear to access it, often a passing opportunity is lost whereas with torque, just bury it. My boss had a 535 BMW which was a goer, but on a busy road, my 3.8 Mk2 Jag would eat it.

Ah, the inverse relationship between reliance on shifting and torque I think you're talking about., at least that's what I'm picking up. I kinda get though but it's a little complicated if you've not fully understood engines. Hence all the various characteristics of each car or bike. I've been enjoying my high revving 4 banger, and I've actually always had them in my Japanese cars/trucks but now I'm curious about these more torqy ones you speak of. I'm guessing V engines introduce this more. And then those flat ones like what are they, the Valkarie and...the other big Honda one. Big ol cruiser.

[dave500]

add in power to weight.

[caluser2000]

dont be scared to ride around town in a lower gear to keep rpm high,dont lug these bikes at less than 2500 and try to keep the revs low,they shine at higher rpm and will be ready to gun it away from trouble if need be,they cruise at 4000,theyll sit at 5000/6000 all day even more,its the way they are.

Dead right. I'm in the 2000-3500rpm range around town.on the 550 in 3nd-4th. Never go in to top gear around town at all.

[Deltarider]

I bought my first bike, a 500\4 in 1973, had 8 or sohc\4s since then, and I have never, repeat, never had a charging issue with any of them. I generally ride with economy in mind, so , no higher revs than necessary, just ride normally. Never had a battery go flat on me. Am I just lucky?

Kevnz, it's just normal. I have thought a lot about this presumed 'insufficient charging system'. You probably have read my comment a dozen times already, so I'm not going to repeat myself. I have given some tips in the past and I specifically wonder if any has fitted a relay triggered by the neutral light so at stops like traffic lights the headlamp would switch to pilot light.
Recently I did some more thinking (always dangerous ) and I wonder if prior to depleting their battery (again), these riders did a lot of 'maintenance' with the bike idling. If they had the bike idling for too long and then start riding, you could still be out of power, if you have to wait at a few to many traffic lights. I myself never had a problem and always return to the garage with a better charged battery than I departed with (oh dear, there I go again. Please excuse me for repeating myself again here).

[caluser2000]

But you and your alter ego are "special" Deltarider"

[Deltarider]

Maybe go for a ride again, Caluser, but please ride safely and don't fall off 'cause we need you here.

[caluser2000]

Maybe go for a ride again, Caluser, but please ride safely and don't fall off 'cause we need you here.

A lot of use don't have the advantage of using an autoban on a daily basis.

And yes I will be going for a ride today. Thank you very much for suggesting that.

At least in NZ you don't have to go too far to find decent riding roads instead of riding on autobans on a regular basis. I imagine it must be boooooooring to say the least lol.