Perhaps a silly question about Highway or Interstate cruising speed

[qurtrn10]

The Buell is my first bike, which I bought earlier this year. All of my riding has been in town.
I'm now at the point where I feel comfortable taking it on a small day trip (an hour or two away from home).
With a stock '03 xb9, how fast should I go on the highway? If I hold 65-70 for a length of time, do I have to worry about holding 3k, 3.5k, or 4k and over heating the bike? What do most do for long drives?

 

[MikeyLawless]

Sometimes i do 90 on my half hour to an hour ride to school and never have any problems. Especually this cooler time of year.

 

[fishxb12]

Never a silly question if it has to do with blowing up your bike,lol. You are fine. They are air cooled engines. As long you have the proper oil level, should not have any issues. People take these bikes on long road trips all the time.

 

[user_deleted]

think of it in these terms which are automotive terms but apply to any motor:
an automobile with any configuration motor that has a red-line of 6000rpm can sit there and cruise at 3000rpm which is 1/2 its red-line for 5 years. an exaggeration but you get the point. same applies to your XB9. at 70mph it is spinning roughly 1/2 its factory redline.
you can also get technical and think of your motor speed in terms of piston distance calculated in feet per mile. take your XB cylinder bore and multiply it times your cruising rpm then divide by 6. you'll find it's a very low number which correlates to longevity.

 

[qurtrn10]

Thanks all. I'm just used to cruising around 2k on the bike and in my cars, so holding a higher rpm is just out of my norm. I'm going to take it out today, and not sure where I'll end up.

Thanks again!

 

[mrlogix]

lunatic: I am continually impressed with your knowledge. The admins will not let me give you another rep point (said I have to spread it around). Anyway, it's nice to see that this forum has as many technically qualified members as we do. A lot of forums I wouldn't wish on my worst enemy.....

 

[fishxb12]

I got a rep point for lunatic [up]. Very cool info!

 

[user_deleted]

lunatic: I am continually impressed with your knowledge

thanks very much for the kind words john. i really appreciate it my friend.

I got a rep point for lunatic

fish: what i posted is a standard formula for computing how hard your motor is working, how long it is likely to survive, and how much internal stress is being placed upon the piston/cylinder/rings/wrist-pin/con rod/con rod big end bearing assemblies. a simple # to generate is a 327 chevrolet V-8.....or the 302 cube Z/28 of 67-68-69 vintage. both motors had a 4 inch bore. 4 inches X 4000rpm divided by 6 = 2666 feet per mile in piston travelled distance. a fair amount of cruising rpm for a vintage V-8 but not all that much actual piston speed. to put it in perspective a 358 cube nascar motor at talladega held on the mat all afternoon will generate approx. 6300 feet per mile piston speed and live for 500 miles and change but that's about it. a cummins turbo diesel dodge loafing down the interstate @ 2100 rpm only generates approx. 1750 feet per mile. and we all know how long those motors live.

 

[jetlee]

Despite his vast knowledge (i do mean that, I even repped you for the formula), I know lunatic hates my corrections...but...shouldn't it be stroke instead of bore, since the stroke is the length the piston moves where the bore is merely the diameter?

On my 07 9R, I ride for about 45 minutes each way to/from work around 4krpm. Haven't had any serious issues yet.

Use a good oil, change on time and you should be fine.

 

[go cytocis]

No risk of damage at sustained freeway speeds.

I'm just used to cruising around 2k on the bike and in my cars, so holding a higher rpm is just out of my norm

If anything, you're at greater risk of engine damage while you're lugging around town at 2000 rpm. At low revs the oil's not up to full pressure or circulating fast enough to optimally cool the motor.

Don't be afraid to give it some revs!

 

[WIGGLE2]

I know lunatic hates my corrections...but...shouldn't it be stroke instead of bore, since the stroke is the length the piston moves where the bore is merely the diameter?

I THINK that's what he meant....the 327 had a 3.25" stroke and the 302 had a 3.00" stroke. Both shorter than the diesel he suggested. But yes....YOU are correct.

 

[BuellyBagger]

I've gone from fuel full to near empty straight through averaging 80 mph non stop. in80° to 90° weather. On a 1203, but you get the point, you will be fine.

 

[mrlogix]

Yes, it is in reference of stroke not bore dia. I didn't even notice the mistake, just started to read the formula and my mind filled in the blanks as I cruised right through it. I'm sure that it was a typo on his behalf.

 

[jetlee]

I THINK that's what he meant....the 327 had a 3.25" stroke and the 302 had a 3.00" stroke.  Both shorter than the diesel he suggested. But yes....YOU are correct.

I'm not arguing his logic or intent, it's actually pretty neat and I'd never heard of that; I'm just clarifying which measurement is to be used.

 

[user_deleted]

yes....i meant stroke. my apologies. to calculate it you do NOT measure the cylinder length...you measure from absolute top dead center to absolute bottom dead center.

 

[UMDterp13]

All tolled, Buells are simple & made by simple people hahah
XB12 stock gearing 5th gear ~ 20mph per 1,000rpm

XB9 stock gearing about 17.5mph per 1,000rpm. In 5th gear

XB12 gearing limited to 140mph
XB9 to about 120.

I regularly cruise 80mph on any buell I'm on, I live in sortof country of southern MD. 60mph then 80 on highway 3900 rpm on my uly.
4500 on the xb9. Takes it like a champ.

Did 12hr one day, boring I know but I had to be somewhere, all 95 up the east coast FL to MD, that bike still runs fine, it never went below 75mph except gas stops every 180-190miles (Ulysses 45-50mpg)

It has seen 131 GPS at least 2x as well as video run to 126 on speedo... Plus just about anytime my right hand gets control over my mind, it sees 100... Moral of the story? I'm not selling that one so you don't have to worry about seeing that motor for sale at least.

Still runs fine & yea those bags hold on just fine

 

[WIGGLE2]

XB9 to about 120.

He's never topped out a '9'.

 

[agfish18]

He's never topped out a '9'.

True, My old 9R used to get to ~140...

 

[konarider94]

mine will do 160

 

[UMDterp13]

Stock xb9 on v box data was under 130 on every run or 210kph for the confused people