Questions about FJs / Xs

[TopCatGr58]

Originally posted by John
I have been elbow deep into both the XS and FJ engines, and I can tell you the only thing they have in common is the crankshaft main bearings. The FJ engine is a 4 valve per cyl engine, and it rotates backwards compared to the XS. I'm sure somebody somewhere could find some way to graft some kind of middle drive to an FJ engine.

Hey John,

You been hittin' the pain meds again haven't you! I think it was Audi that was looking for an easier/bolt on way of taking an XS11 to chain drive....like the FJ1100's, not putting a drive shaft middle drive onto an FJ1100!?!? But thanks for the info, I'll be hopefully playing with my spare middle drive unit sometime this year! I have to get BasketCase torn down and put back together for my nephew first!
T.C.

[John]

Not the meds, but

I did just recently complete the on line version of' 'The Eve'lin Woodhed sped reddin' course", and I must have overlooked the that when I started reading.
yeah, that's it... the sped reddin course

[Wildkat]

After looking a little more closely...

at both bikes... I'm even more confused (okay... that wasn't so difficult)

How did you want to do the conversion? I don't see a quick bolt on fix...

Apparently, from what I read in this post, pggg isn't real big on the chain drive for an XS... but I found a link to a thread someone had posted that seemed to do a pretty decent job...
Chain Drive Conversion


I'm sure you've probably already done the search and found some of this stuff already... but just in case you haven't... there are a few more...

Audijunky and xschop posted on their chain drive conversions as well...

[Wildkat]

By the way Tod and Spidey...

I'm going to be keeping my eye on you two...
talkin' about doin' bad things to my baby...
shame on you
ought to be ashamed of yourselves

[pggg]

From pggg 'who in their right mind would want a dirty greasy chaindrive" From Kat, 'apparently pggg isn't real big on the chain drive for an XS...'

ummm.. I'm in my right mind?

[trbig]

I'm going to be keeping my eye on you two...talkin' about doin' bad things to my baby...

Last I heard... you had a NEW baby in Foster Child. C'mon.. you can give up one child in the name of science!?!?

It would give us something to do while Mark isn't drinking your beer! Hey Kat... can you run to the store for us for a little bit.. *Evil laugh...

In all seriousness (I know.. it's rare) What were the specs on the FJ versus the XS/XJ? 79XS11F says the FJ is not as powerful? Is it just the chain drive then that makes Kat's FJ quicker? (Don't know this for a fact since she takes off with no warning.... least Bob Jones gave us warning before we blew his doors off.. Hee hee.. )

I, for one, would not switch to a chain drive even if it gave a 20% boost in performance. There's always going to be a quicker bike out there. When the new ones are making close to 200HP and can lean into a curve 89 1/2 degrees... it's like trying to get a '57 Chevy to run with a Diablo... it just ain't gonna happen. Sure, a souped up Chevy will beat alot of cars out there, but is that really what you're going for? The other couple people you can beat stoplight to stoplight? These bikes are smooth and comfortable cruisers that happen to pack a heck of a thrill in the throttle.. and even back in their day, they were the chit! But that was 25+ years ago. The years have passed, and so have these as a "Super Bike". My horsepower loss by sticking with the shaft drive will get me quiet, smooth, fairly maintanance free power at my wrist for some 100,000+ miles. That's what impresses me about these bikes. Any other bike made around that time... 50,000 miles was wore out.
You're gonna whip 99.9% of any V-Twin bike out there.. no matter the size.... but you're going to lose to most crotch rockets built in the last 10 years... no matter the size. So.... squeeze out every horse you can get from your motor, and get it all to the ground from a chain drive... and a modern bike 100cc's smaller (And most 350cc's smaller) is still gonna whip your tail from light to light AND out on the highway.

Have fun and quit trying to "Prove yourself" with an antique. I have seen the chain wax that isn't nearly as dirty... but I have yet to hear a chain driven bike that I can't hear the chain BEFORE I can hear the bike... Gonna get 100,000 miles out of that chain and sprockets?

Sorry all... had a couple beers and it's late.... may have said too much. Just my 3 cents worth... even though nobody was askin'.


Tod

[pggg]

Trbig, an XS11 easily matches or whips any modern plastic between lights, it's more the torque not horsepower

[trbig]

LOL... I don't know where the info you're getting is coming from, but when a modern 750 is making @ 130hp and doing low 10's in a quarter mile, and a 1000 is easily into the 9's... our machines can't get anywhere near that. Sure, riders will differ and a good rider can beat a quicker bike sometimes, but have you ridden something modern lately? If you're beating these between lights, it's because they are inexperienced, or not trying.

Tod

[John]

Originally posted by pggg
From pggg 'who in their right mind would want a dirty greasy chaindrive" From Kat, 'apparently pggg isn't real big on the chain drive for an XS...'

ummm.. I'm in my right mind?

Pat, Wildkat was being facetious when she posted that link about your chain drive conversion. She did it to show how serious you are about the conversion.

[Wildkat]

Originally posted by pggg
From pggg 'who in their right mind would want a dirty greasy chaindrive" From Kat, 'apparently pggg isn't real big on the chain drive for an XS...'

ummm.. I'm in my right mind?

Life would be pretty boring if everyone were in their right mind... It's those of us who aren't... that make life so interesting... Right Tod?


So all of this makes me wonder (yep... look out!)... What are the advantages of chain vs. shaft for the XS? Why convert (yes... I'll go do a search and see what all has been posted already) in the first place?

The way I ride... the FJ is much quicker off the line... but the XS holds its own in the middle range and even in the top (sort of)... it just doesn't go as fast in the long run. Now I don't ride the XS like some people might (ahem.. won't mention any names here... because there are too many)... I don't push it for speed (that's why I ride the FJ)... so I don't really know what it will do (and probably won't find out)
Twilite rides VERY comfortably around 100 and is EXTREMELY quick off the line... especially with John riding... John's done the 1179 big bore so it has that advantage and Twilite gives the FJ a decent run (at least it did) with that mod... The FJ would still get it in the long run though...
Just seems you have to give up top or bottom performance one way or another...
Sorry... getting off topic now...

So.. to get more to the point with my question (you're welcome )... what advantages do you (Rob) expect to get from a chain drive conversion?

[webbcraft2150]

Before big HP bikes, shaft drive had a parasitic draw on HP, however small it might have been. Shafties were not considered "performance bikes". The loss of HP usually could be felt at top end speeds, a place most people do not ride. Having owned chain drive, and shafties, you would be hard pressed to get me to buy a big bore, chain drive bike. The sheer lack of maintenance needed is enough for me. Would a chain drive XS be faster? Maybe, but only cause you can change the final drive ratio on a chain rig easier. Would it be worth it? That would be up to the rider.


FJ outrun the Twilite Special? Could there be a difference in aerodynamics at sub light speeds that gives the FJ a edge? Dare we even consider the load difference.

[Wildkat]

Sub light?

Who travels at sub light?



As for the FJ outrunning Twilite... well yeah... of course the obvious performance issue with aerodynamics... Twilite runs with a large windshield cutting down on performance too.. but all in all... it's a good, solid running bike and there have been a couple of blasts where Twilite did a pretty decent job keeping up with me...
Like I said... I don't think the XS would be faster in the long run... but under the right conditions... it might do okay against the FJ (but I'll do my best not to let that happen)

HobbyMan and Tod (among others) have proven that stock bikes can really kick some major booty with the right type of rider...

We changed the gearing on the FJ, so I understand the advantage of that as well... but even gaining in the bottom end (don't say it Tod) I had to give up some in the top...
of course... I haven't run it that high in awhile so not sure exactly how much...
My speedometer cable was only recently put back on after some problems... so I don't really know how fast I was going... ahem...

[79XS11F]

For me the chain drive option is not just to get the extra horses to the road it is also to avoid the "settling" effect of the shaft when one finds themselves having to let off the throttle unexpectedly in a corner. There is also added weight loss, bigger tire options and the ability to change gear ratios. there are in my opinion advantages and disadvantages to both set ups. I only asked the question about an easy switch out because sometimes the obvious and simple solution is overlooked.
There are others here who have gone to the trouble to chain drive their bikes and i am sure that for them there was a reason. It can't be just a "make work" decision.
Rob

[Wildkat]

That's cool...

I was just curious...
The difference between the two bikes, for me, is definitely very distinct and I can see the advantages of doing the conversion... It seems you have a lot more options with a chain drive... I think I was more curious about what actual benefit there was to it or if it was more just personal preference (remember... I'm still a novice here)...

I need to go back and read some of the posts a little more indepth and see what the outcome was on the others, I guess...

ANYway


So are you definitely doing the conversion? or are you still in the planning stages?

[pggg]

Originally posted by John


Pat, Wildkat was being facetious when she posted that link about your chain drive conversion. She did it to show how serious you are about the conversion.

John I know Kat was being facetious, as I was facetiously being facetious myself

Trbig, a drag between traffic lights and a drag down a 1/4 mile strip are two different things... watch a tight street circuit motorcycle race some day, you'll see what I mean... hell I've seen old XR500's on slicks clean up R6's, fireblades etc.. but of course you're right, it's all down to the rider