Question about RPM range for gears

[popmac]

This is my first bike (82 Maxim), really only starting to get some good usage now and only the third bike I've rode at all - a TU250 for my safety course and a V-Star 650.

I've been doing some reading and constantly see people saying that these bikes aren't really alive until around 7k RPM. Heres one that caught my interest specifically:

Your only option is to change the CS sprocket for a 17T. This will drop the RPM by about 500. It's also likely to reduce economy, as the DOHC likes to rev. Above 7000 is it's happy place. Below 3000 is lugging the engine.

The reason I am mostly curious is because my fuel economy really seems to suck compared to other people here - I'm getting around 34 mpg but keeping in line with the other bikes I've rode, getting the bike out of 1st pretty well as soon as you're moving then keeping it well under 7k RPM, cruising between 4 and 5k. At 7k the bike absolutely screams - not bad for a busy road but enough that it would likely make my neighbours hate me.

I just did a quick run around seeing what I am looking at for gears running up to 7k. 1st gear at 7k is 40 km/h, second gear at 7k is 60 km/h. 60 km/h in 3rd gear is 5k. Is this normal? Most of my city roads are 60 km/h - should I be crusing my city streets in second at 7k?

I just put on a new chain and sprokets, I don't remember the teeth but I went with stock.

 

[NewHavenMike]

Why would you ever cruise in 2nd at 7k? I changed my rear sprocket because I ride at 70-80mph on the highway and maintain that for 45 miles each way.

When Im cruising, I shift around 5-6.5k. I regularly shift at 8.5-9k on a daily basis though.

These bikes like to rev and need to be revved. The V twin your used to has a lot of low end torque and is completely different. Those thing probably redline at 5.5k. Our bikes get power at the minimum of 6k.

Also when Im cruising, I keep the rpm needle right around the top of the gauge, which is something like 5.5-6.5 k. That seems to be the sweet spot for me.

 

[popmac]

Why would you ever cruise in 2nd at 7k?.

My in city speed limits are mostly 60 km/h and I've read here multiple times from a bunch of people that the bike doesn't really have power until 7k, so at 60 thats 7k in 2nd or 5k in 3rd. I'm new to the XS400 and bikes in general so thats why I'm asking - not sure where it makes sense to sit with the bike.

I quickly booted out to the highway to see what its like shifting at 7k and up as opposed to where I was. Going 100 km/h in 4th is right around 7k. Previously I was doing 100 in 5th and trying to accelerate up from there was quite difficult, which had me worried about being on the highway and needing to speed up. Keeping it in 4th I could actually get up to 110 from 100 quite quickly, so thats good to know.

 

[NewHavenMike]

Just ride it normally.. Just because you make the most power at a certain RPM range, doesn't mean you always have to be there.

I ride and cruise with rpms as low as 4k sometimes. Of course the engine has no power at all and its borderline lugging, but its OK. AS long as its not lugging badly, this is where you can get pinging and all that stuff..

If you want the fastest acceleration and the most power, you need to be shifting right at about redline, which means the next gears will catch very high in the rpm range. If youre cruising, you don't need power and you can shift whenever you want.

Riding on the highway is very different. This is where the small engine capacity starts to lack, especially when you need to make a pass. You need to adjust to the performance of the bike and downshift and give yourself enough space to make a good pass. I avoid passing on the highway but I will pass tractor trailers as fast as I can.. they kick up a ton of dirt, limit visibility, and those retread tires scare the crap out of me..