A more power

[racerrad8]

...... Hi,.. I am in the process in rebuilding my motor, [right now it is at 1219cc, no sleeves] .... I have had a lot of talks with several people related to FJ's [ in the past month]. From the Legend car's to Hank Scott and Randy [ in the way of .PM.]. Hank makes it sound OK, to install sleeves in the motor. But, I have also, had a conversation with a Yamaha dealer mechanic, in my area.....he has a 86 FJ 200hp turbo drag bike..... He is telling me, with passion, DO NOT install kits with sleeves. I would have nothing but problems, mostly oil leaks.
..... For the street, all I need is a set of good cams, headwork and a set of good carbs.
....... also, he is saying,.... the lower cc motors can run with the bigger cc motors, if done right. and be more reliable, and cheaper,............. No replacement for displacement ?? 
...... So, If I can,.....get the thoughts on the ones, that have the kits with the sleeves in their motors.
                                thanks, Jeff

Jeff,
       I have to say after building close to 150 engines in my FJ career I have never experienced an "oil leak" due to a sleeve. Frankly, I cannot even give you a reason why there would be an oil leak issue with a sleeve. Heck, Yamaha installed sleeves to begin with.

I have probably installed close to 200 sleeves and I have had no problems to this point. I will say I have had several engine come in from other builders where the sleeve were not installed correctly, but they did not leak oil...Hell, we bore out the thin wall nikasil sleeves that come in the XJR1250 and install thick wall steel sleeves to reduce cylinder distortion and prolong ring seal.

There is a great amount of gain by increasing the amount of fuel and air into the engine which will increase the power, but the best engines are a combination of all of the right parts to get optimum performance.

No offense to you Yamaha dealer, but he really doesn't make much sense with that comment.

Randy - RPM

[Brook]

...... Randy,... I am just repeating what he told me. But, I did see something about oil leaks with big bore kits in the Rod Mumford write up. it said, you must fill the holes ?? or you will blow the head gasket.
and that is what Mike the Yamaha mechanic said. ...

.. I still would like to get a 1349 kit, but, what scares me is finding the machine shop in my area that has experience with FJ motors. Because, I know the cases have to be cut.
                               
                                        Jeff
   

[SlowOldGuy]

Having owned both FJ 11 and 12, I dispute the notion that there is very little performance difference between the 2.

The fact is to ride on the street - the engine torque characteristics are like cheese and chalk, even more so than you would think with only less than 100cc  and 5 hp difference.

12's have much more useable roll-on grunt down low which makes for less gear changing especially round town in traffic and overtaking.

Before you believe such rubbish, PROVE the above for yourself by taking even a standard 12 for a ride to compare the difference will surprise you.

I guess "opinions" vary.  I currenty OWN an '85 1100 and a '93 1200.  Been riding the '85 for 25 years and the '93 for over 10.  

If the 1100 lacks anything in low end torque, it makes up for it with the slightly higher gearing.  So maybe the 1200 is slightly stronger, but it's not a night and day difference.  I can ride them back to back and the only thing noticeable is the rubber engine mounts of the '93.

The point I was trying to make was instead of spending big bucks and investing a ton of time trying to turn the FJ into something it isn't, just go buy something else.   There's always someone faster out there, no matter how much you spend.

DavidR.

[Dan Filetti]

I guess "opinions" vary.  I currenty OWN an '85 1100 and a '93 1200.  Been riding the '85 for 25 years and the '93 for over 10. 

If the 1100 lacks anything in low end torque, it makes up for it with the slightly higher gearing. 

I was waiting for that from the second I read his comment. 

[oldktmdude]

  I'd have to agree with Westozfj having just converted my '85 1100 to a 1200 by simply fitting a standard 1200 block and pistons. The difference is very noticeable. The bottom to mid range torque has increased alot. The fact that some of you own both 1100 and 1200 bikes and say the difference is not so noticeable, maybe due to the 1200 being slightly heavier and having a taller fairing?     
                                                                                                                              Pete.

[Dan Filetti]

Folks-

Displacement is important.  But 100 CC?  Seriously?  He's what I do know: my '85 FJ1100 would show an *indicated 156 at top speed.  My '02 GSXR750 shows and *indicated 178.  I know both of these are optimistic but the Gixxer is clearly faster, in all but the real world roll on power where the power delivery characteristics of the FJ is markedly better than the GSXR. 

But just stop and think about it, if a 750 can out run an 1100 in most cases, (but not all flame away if you must) then there is more to it than displacement. Gearing, to David's point, curb weight, wind resistance (at higher speeds), and engine tuning, spring to mind.

I'm thinking that folks that say they can 'feel' a significant difference really 'feel' a bit artificially superior because of their extra 100CC.

Commence flaming.

Dan   

[andyb]

My opinion (which is worthless as my garage is full of racing FJ bits) is that you should make sure the bike is running as well as it can run, as that's where you can often get a fair bit of power for not much money at all.  And then, a gearing swap is going to be far and away the best thing for increasing thrust to the ground.  After that, smart money is on getting something with more power (and/or lighter weight) in the first place.

The only thing I'll point out to Dan is while a 750 is easily a bunch faster at the top end (probably an honest 160ish vs a realistic 145), the roll-on performance is what many folks want.  The one that always bothers me is when people dont' compare apples to apples.  An FJ at 3k makes pretty good torque.  A well built cruiser will make far more at 3k.  The difference is redlines and gearing.  If you want a really fun comparison, sit down and work it out by percentages and compare them at the same actual speeds (fastest way to double torque is to halve the gearing).  So compare bike A at 30% of redline in a gear that goes 100mph even against 30% of redline in a gear that goes 100mph... it probably won't be the same gear, if the bikes are different enough.  When you start doing that, you really start to wonder, because you can clearly see that so many of the "really torquey" engines are actually utter crap and geared comparably short against a relatively "peaky" engine.

In the case of a 1100 vs the 1200 stock engines, you'd have to have both on comparable gearing (which the FJ is artifically sensitive to if you're measuring at the dragstrip, take note benchracers!).  However, when you're talking about going from the stock compression and higher mileage older 1100 to a freshly-pistoned 1200 where everything's in good shape and working as intended, the back to back difference should be quite easily felt.  Remember that these are not new bikes by any means, and they don't all run the same (see original point, get what you have running as well as possible for what it is!).

[hpras]

I have 2 cents.  I was at the dragstrip with my 87 FJ.  Hot evening at 800m, so the times weren't great.  Also, I'm just not that good at it as I don't do it more than once a decade.  Was up against a GSXR750, looked like a newer 06-07.  I thought I'd at least get half track on him whereupon he'd scream by me.  Didn't happen, I was behind the whole way on a fairly good hookup.  A quick guess is that his lower weight beats my greater torque.  I'd have to assume though that if we both rolled out at 3000rpm and whacked it, I'd walk away from him for the first bit anyway as I'd be in a meatier part of my torque band.

Anyways, I don't discount 100cc, or 91cc.  It is 8% greater displacement, not insubstantial.  Might not show at the peak if the breathing apparatus is the same, but would definitely show through the middle.

[andyb]

Partially that's riding skill too.  Go to the track enough and you'll abuse machines that should have no right to see your taillight.  Once in awhile you'll catch someone riding their machine absolutely flawlessly, and they'll beat you with something that should not have any chance at all.  The FJ is nice as it's a fairly easy bike to launch relatively well, compared to a peakier powerplant.

[hpras]

I did have a hard time hooking up on quite a few of my runs.  Track was kind of slippery, most of the bikes there were having trouble.  Even on a low rpm launch I'd break loose as the rpms came up and I got off the apron.  Usually had to short shift out of first.  My best run of the night was my second one, after that I couldn't find the sweet spot anymore.  Here's what I posted on the PG Vintage Bike Clubs website about the evenings races.......

Roseanne managed a best time of 11.89s and a top speed on 114.3, though not on the same runs.  The best time was on my 2nd run, best speed on my 3rd.  All downhill from there as the track became slipperier.  Everyone seemed to have the same trouble.  I ran those number in the handy dandy calculators and currently my bike is putting out about 90hp.  The time corrects due to weather down to 11.3s and 120.2mph.  Running that back into the handy dandy calculator has Roseanne putting out 103hp at standard conditions.  The review from the July 1989 edition of Cycle Magazine had the dyon saying 102.7hp and it running 11.03@123.7, so Roseanne isn't doing too too bad for have 93,000km on the clocks.  An earlier test of an FJ pulled out 10.78@127.1, I'm guessing that one was a ringer.

[Dan Filetti]

Your point Andy is well taken, the 1100's are inherently older and likely to be in a lower, age-related state of tune, but assuming you had a mechanically pristine stock 1100 running next to a mechanically pristine stock 1200.  I'm thinking the weight and gearing difference between the two are going to make the power related 'feel' fairly hard to distinguish, not impossible mind, just fairly hard to.

Dan

[racerman_27410]

Well i guess everyone know which side i'm taking on this matter 

..... yes you can buy a faster machine than the FJ will ever be....

yes building Brutus was very expensive.... but it didnt cost as much as a new Busa.
In the end i have wound up with a motorcycle that has an RDI of Zero (No one is gonna roll up bside me on a bike exactly like it )

A bike that puts a shit eatin' grin on my face (and most bikes behind me) every time i twist the throttle

A bike that i can still enjoy just looking at.

spending the money on the engine build made (and still makes) perfect sense to me.   




KOokaloo!

[Travis398]

If you had a worn 1100 and rebuilt it to a 1200 I would believe there could be a noticeable difference.

but if I ride my 1100 and then a 1200 (assuming it is not Brutis)  I don't feel it. Maybe the weight and gearing is responsible,

but than again I'm not chasing .001s  

[Brook]

..... racerman_ 27410,... I could have not said that better myself,.... If you have a Busa or a GSXXR or a R1. What do you have?..... Just another Busa, Gsxxr or a R1....

...When I, pull-up on a Saturday night,.... where is a group of guys on thier bikes.......I do not have to worry, about seeing another bike like mine?

...... 1219cc^^^ 1314cc, 1349cc ??
...... I am getting a hard-on, just thinking about it !!!...LOL   
 

[racerman_27410]

..... racerman_ 27410,... I could have not said that better myself,.... If you have a Busa or a GSXXR or a R1. What do you have?..... Just another Busa, Gsxxr or a R1....

...When I, pull-up on a Saturday night,.... where is a group of guys on thier bikes.......I do not have to worry, about seeing another bike like mine?

...... 1219cc^^^ 1314cc, 1349cc ??
...... I am getting a hard-on, just thinking about it !!!...LOL    
 

1349cc of course   ....      115 lb/ft of torque IS the icing on my Kookaloo cake!  

Kookaloo!!!!!!!!!!!!!!!!!!!!!!