So an XB9 runs 984cc, makes 70ft-lbs @ 5500rpm and 92hp @7500rpm. Costs roughly $8900.

an XB12 runs 1203cc, makes 84ft-lbs @ 6000rpm and 103hp @6800rpm. Costs roughly $10,500.

So for an extra $1600, you get a 219cc bump, 14ft-lbs more tourque, and 11 more hp, but a lower redline and a lower tourque curve.

I guess I'm just a little curious what kind of power an XB9 could make with $1600 worth of work into it, and if the shorter stroke gives it any kind of advantage other than a high redline.

For under $1600 we could do stage 2 head porting($850) which will give you probably 10 more hp all by itself. Then throw a Micron exhaust($799) and you should have a really nice screamer. The short stroke allows more rpms so you actually have more top speed than a 12.

Didn't think of the top speed.

I also wonder how much a 9 could benefit from a custom fuel map. My friend with his 12 just had it done and gained a good 30hp at the wheel with a custom map. The baseline was run with a D&D exhaust.

I'm also kind of wondering all this because I think it would be kind of neat to have a short-stroke XL as well...something that would really hum. I keep thinking about a Chevy 327 vs. a DZ302. What a difference a little headwork, cam and short stroke crank made in that engine.

Agree that twins aren't about top speed. When I had my Ducati, I pretty much had to relearn how to ride, because up until then all I rode was inline-4 Japanese sportbikes. Street twins are all about low to mid-range grunt, and being able to not have to change gears as often and motor thru those corners instead of shifting and squirting from corner to corner. From what I remember about road tests on the XB12R, they said it didn't take as much effort as the XB9 to hustle thru a road course. I still like the XB12R, in black, with those gold wheels, and a good exhaust and intake filter. That would probably be a decent substitute for the '93 Ducati Superlight I used to have.

Who says v-twins aren't about top speed? 205.642mph at Bonneville baby!!! :)

Dan...what exactly is Burt Munro's record? Is it just any streamlined motorcycle under 1000cc? Seems to me this record would have been broken by now. What's the deal?

Land Speed Racing is a such a draw to me...too bad I'm too far away from it all...

There are all kinds of records in many different classes. It all depends on engine size, type of engine, type of bike etc. I am no expert on the subject. Hopefully Aaron will chime in here and give more information as he knows a whole lot more about it than I do.

The SCTA/BNI records can be found here:

http://www.scta-bni.org/Bonneville/records/BNIrecs_bikes.htm

Burt's record is in 1000cc streamliner-fuel.

That record is said to be cursed. People who have gone after it generally crash.

so what would an xb9r set up with the actell 3 13/16" cylinders make for power in comparison to the 12r

This is a converted XB9 with 12 crank and Axtell 3 13/16 engine kit we did for a customer:

http://www.nrhsperformance.com/images/drsamminnich.gif

This is a converted XB9 with 12 crank and Axtell 3 13/16 engine kit we did for a customer:

http://www.nrhsperformance.com/images/drsamminnich.gif

Do you have a Dyno run of an XB9 with just headwork, and maybe cams and exhuast?

The SCTA/BNI records can be found here:

http://www.scta-bni.org/Bonneville/records/BNIrecs_bikes.htm

Burt's record is in 1000cc streamliner-fuel.

That record is said to be cursed. People who have gone after it generally crash.

Well now you planted the seed...gotta build a bike now...

I take fuel is anything but gasoline? I have a hard time believing that someone coudln't build a 1000cc streamliner that was capable of breaking 200mph. I guess it really is cursed.

Oh yeah, in this day and age, it's a soft record, at 183 and change.

If you notice, MPS-F 1000cc is 223 ... and that class allows less streamlining. But that's a pretty strong record.

There are so many classes at Bonneville, that it's sort of that way. Far more classes than there are racers. So some records are soft (or even non-existent), others are tough.

I do know that people have gone after that record and crashed, though, and then abandoned it.

On the class designations, the left side is the bike and the right side is the motor.

For example:

MPS-PG is "Modified Partial Streamlined" bike, "Pushrod Gas" motor.

For bike types, there's:

P (production)
M (modified)
MPS (modified partial streamlined)
A (altered)
APS (altered partial streamlined)
S (streamliner)
SC (sidecar)
SSC (streamliner side car)

For motors, there's:

P (production)
PP (production pushrod)
G (gasoline ... must use the stuff sold at the event)
F (fuel, anything else, or nitrous)
BG (boosted gas, i.e. turbo or supercharger)
BF (boosted fuel)
PG (pushrod gas)
PF (pushrod fuel)
PBG (pushrod boosted gas)
PBF (pushrod boosted fuel)
VG (vintage gas)
VF (vintage fuel)
VBG (vintage boosted gas)
VBF (vintage boosted fuel)

and probably a few others.

And of course, a whole bunch of displacements: 50, 100, 125, 250, 350, 500, 650, 750, 1000, 1350, 1650, 2000, 3000 and unlimited.

So when you work out all of the possible combinations of those, and subtract out specific combinations that aren't allowed (for example production frame must run production motor), it comes out to about 1900 classes. There are between 350 & 400 records on the books.

It's kind of ridiculous, but I don't make the rules.

The mainstream frame classes are M, A, MPS, & APS. The mainstream motor classes are G, F, PG, and PF. Combinations of those probably account for >80% of all entries.

We've historically run M-PG, M-PF, MPS-PG, and MPS-PF. They made a rule change recently though that bumps both our race bikes to the "A" frame category (M frames must use a motor from the same manufacturer as the frame, and both my race motors use S&S cases).

So you're telling me that someone with enough time and money could technically win something in the neighborhood of 1500 records?

I glanced through your link there and did notice that there seemed to be an awful lot of classes - more than neccesary I think, but like you said, we don't make the rules.

I think it would be so cool to build an LSR bike - just to have the oppurtunity to push a machine to it's absolute limit. I just can't even fatham the amount of time and expense that goes into a venture like that. I take there aren't too many "casual" racers showing up to these events?

You can show up to run at certain speeds. There are "clubs" in which you cannot go over a certain speed like the 130 club, the 140 club, etc. You are not trying to set a record just push your bike to what you think it should do.

It's not a competition except with yourself.

Actually, land speed racing is VERY grassroots. It's populated with your typical gearheads, people with a lot of creativity and natural engineering talent, who tinker and come up with stuff and bring it out and try it. It's really the reason I like it so much. When you get too much into professional racing, it becomes much more about business. Bonneville remains one of the last bastions of true amatuer grass roots racing.

Take a look at some of the pics I put on this thread for an idea of the kinds of things you see at Bonneville:

http://www.xlforum.net/vbportal/forums/showthread.php?t=13517

We better quit hijacking this thread now ;)

If you want to modify it, I'd go with the XB9.

If you want to just buy it and ride it, I'd go with the XB12.

Aren't I allowed to hijack my own thread???

Anyways, thanks for all the info - I may have to give this a whirl someday...would make for a cool roadtrip if nothing else.

I'm pretty sure highjacking of one's own thread is allowed in international internet play! So heck yea, let's make your bike fast then come out to play with us on the salt!! :)

I had a college profesor at FSU, Scott Guthrie, who has held his fair share of land speed records. Used to ride Yamaha TZ-750s. Not sure what he's ridding today.

It would be nice if you get your hands on an XBRR roadrace motor. That thing would scream on the salt.

I was actually wondering if one were to retain the xb9 crank, and going with the larger axtell cylinders. With the different stroke length of the xb9 and the axtell 3 13/16" cyl's, what would that do for performance?

short stroke of the 9 giving it higher reving ability and the larger dispacement of the axtel's, could be a fun ride in a completely different way than we are used to.

Oh yeah, Scott's a fixture at Bonneville.

Dean, that's our "1200 kit" for the XB9 (it actually comes to 1169cc). How much they make is just a function of how much we do. Here was one we did that ran pretty decent:

http://www.nrhsperformance.com/images/drjholmes.gif
It has Red Shift 585's and a bored throttle body.

Here's another:
http://www.nrhsperformance.com/images/drhchdxb12s.gif
This one used the stock cams with a stock throttle body.