winter time mods

[Mark Olson]

It is that time of year again , the holidays are upon us and the 86 fj is just about ready for it's winter nap.

so as I can't leave well enough alone. I must once again give in to my modification urges.

I will be installing ........
fzr front wheel
new rotors
fjr clutch master (this will fix my mismatched lever disorder)
spin on filter
clutch slave rebuild
new chain and sprockets
new rear axle
perform normal maint and cleaning and polishing.

that should keep me busy for a few days.

What are the rest of you gonna do?

[LA Mike]

Mark,

You live in California there is no such thing as winter, we ride can ride 365.....

[andyoutandabout]

Mark, you know what I'll be doing soon, but the bike will only (read should only) be out of service for a week tops. Come on - it's like L.A. Mike says, we're year round here. Just come down to Napa instead of Tahoe. Oh yeah, like anytime.

Andy

[fj1289]

My winter project?  Sorting out the chaos caused by the drag race bug! 

First order of business is the get the street bike FOCUSED ON THE STREET again!  That includes rebuilding the original 1200 lower end, freshening the bores and rings on the 1314 kit, and 16 new (straight) valves in the head, and most importantly, having the valve reliefs in the pistons flycut to fit the oversized valves (so I don't have to replace another set of valves with less than 100 miles on them... ).  Hope to get the bottom end buttoned up tomorrow.  Then it'll be ready when the top end parts come back from the machine shop.  Chassis wise - fit the rebuilt Wilbers shock and replace the fork springs.  Have a broken mount welded on the Givi wing rack, fit grip warmers, break out the electric vest... Hopefully this one will be ready to roll in mid December, January at the latest!

Second order of business is to rebuild the parts bike as a dragbike.  Only have everything left to do on that!  Chassis wise have cut '01 R1 forks with '02 trees (only 25 mm offset), CBR900 front rim,  FZ1 swingarm with adjustable 0 - 6" extensions welded on, '01 R1 rear rim (17x6), Elka drag shock for Busa (modded to fit FJ/FZ setup).  Engine wise have to sort out a parted drag project from a couple of years ago.  The good: Carrillo H beam rods, aftermarket big block with 90 mm sleeves (being fitted for 85mm JE's) and a big valve ported head.  The bad: pitted bores in the block (thus overboring from 83 to 85 mm!  ), two bad rod bearings - one severely worn, one spun (probably have to have that rod rebuilt), and the porting in the head looks like crap (looks like unfinished SLOPPY epoxy to "correct" some mistakes [vice actually using the epoxy to change the port shapes]).  Hopefully this one will be ready to run in anger when the tracks reopen in spring.    


Chris

[Mark Olson]

Mark,

You live in California there is no such thing as winter, we ride can ride 365.....

I know mike thats what makes it  difficult to get any work done on the fj.

[Mark Olson]

Mark, you know what I'll be doing soon, but the bike will only (read should only) be out of service for a week tops. Come on - it's like L.A. Mike says, we're year round here. Just come down to Napa instead of Tahoe. Oh yeah, like anytime.

Andy

I just may head your way after the tinkering is done, I was still out riding it with the bad slave and fanning the clutch at the stoplights.

[threejagsteve]

Yes, it's true that we don't have real winters here, but when it's 48*F and raining, riding ain't much fun!

Aside from the 3.5" and 5.5" wheels and a few other small things I've already mentioned, there's one experiment, not really a mod, that I'm trying to plan.

Like many here, I've done the monobloc calipers/14mm master cyl./SS lines upgrade.

As I was putting them on, I saw that two of the pistons are the same size as the '89+ FJ 4-pot calipers, and two are smaller. I also noticed that the pads for the monoblocs have the same width, but are shorter in length.

Now, granted that the monoblocs are lighter. I haven't weighed 'em yet, but I will.

It's said that the stock calipers "flex." But they're held together with four good-sized bolts, so tightly that they don't leak at the seam. Perhaps under extreme, racing-type conditions there might be some flex, but does it happen under normal, even aggressive, street riding conditions?

And since the dawn of disc brakes, larger piston diameters and greater swept area (= pad contact area w/rotor x no. of pads) have always been considered better and more powerful brakes. Here we have a case where calipers with smaller pistons and less swept area are being acclaimed as "better."

I began to wonder how much of this braking improvement was really due to the monobloc calipers, and how much was due to the 14mm master cylinder being installed (usually) at the same time. I haven't found a single case where someone has spoken of mating a 14mm m/c with the stock '89+ calipers. 

So I started thinking about how to design a comparison test since I now have functional sets of both calipers. (Thanks, TRoy!) I could just put both sets on the bike with the same m/c and compare that way, but I want to do a more scientific bench test.

Of course I can hang a weight off the lever so the lever pressure doesn't vary. But I haven't been able to think of a good way to spin the wheel. Connecting it to an electric motor is the obvious answer and I may do that in the end. But the thing about an electric motor is that as it is slowed down by a load, its torque increases. That's exactly the opposite of what happens in real life, where as the bike slows down the forces acting on the brake decrease with decreasing momentum. A clutch arrangement disconnecting the motor once the wheel is spinning is another possibility, but that leaves me with only the momentum of the spinning wheel - a tiny fraction of the momentum of the whole weight of the bike plus rider.

So for the time being I'm stumped... Anybody have any ideas?

[andyb]

Still finishing my FJ project.  Needs the head finished and assembled, the motor stuffed back in, and then I get to face the specter of tearing the subframe apart and improving the fuel system to handle the load.  It's getting there, I refuse to work on it when I'm tired though, so I haven't gotten a whole lot done (the head is about half done right now).


FJ1289:  Dude, 1448cc?  You nutcase... in a good way

[Mark Olson]

Yes, it's true that we don't have real winters here, but when it's 48*F and raining, riding ain't much fun!

Aside from the 3.5" and 5.5" wheels and a few other small things I've already mentioned, there's one experiment, not really a mod, that I'm trying to plan.

Like many here, I've done the monobloc calipers/14mm master cyl./SS lines upgrade.

As I was putting them on, I saw that two of the pistons are the same size as the '89+ FJ 4-pot calipers, and two are smaller. I also noticed that the pads for the monoblocs have the same width, but are shorter in length.

Now, granted that the monoblocs are lighter. I haven't weighed 'em yet, but I will.

It's said that the stock calipers "flex." But they're held together with four good-sized bolts, so tightly that they don't leak at the seam. Perhaps under extreme, racing-type conditions there might be some flex, but does it happen under normal, even aggressive, street riding conditions?

And since the dawn of disc brakes, larger piston diameters and greater swept area (= pad contact area w/rotor x no. of pads) have always been considered better and more powerful brakes. Here we have a case where calipers with smaller pistons and less swept area are being acclaimed as "better."

I began to wonder how much of this braking improvement was really due to the monobloc calipers, and how much was due to the 14mm master cylinder being installed (usually) at the same time. I haven't found a single case where someone has spoken of mating a 14mm m/c with the stock '89+ calipers. 

So I started thinking about how to design a comparison test since I now have functional sets of both calipers. (Thanks, TRoy!) I could just put both sets on the bike with the same m/c and compare that way, but I want to do a more scientific bench test.

Of course I can hang a weight off the lever so the lever pressure doesn't vary. But I haven't been able to think of a good way to spin the wheel. Connecting it to an electric motor is the obvious answer and I may do that in the end. But the thing about an electric motor is that as it is slowed down by a load, its torque increases. That's exactly the opposite of what happens in real life, where as the bike slows down the forces acting on the brake decrease with decreasing momentum. A clutch arrangement disconnecting the motor once the wheel is spinning is another possibility, but that leaves me with only the momentum of the spinning wheel - a tiny fraction of the momentum of the whole weight of the bike plus rider.

So for the time being I'm stumped... Anybody have any ideas?

Steve, I would think a standard 60 mph to a full stop distance test would give you your answer.

I personally went from stock 86 brakes to blue pots with stock master ,then to fjr master and the effect was an increase in braking ability  at each change. I think the blue pots just look better anyway.

have fun with your mods and whatever meds you are on that keep you up at night are giving you strange ideas and making you tweak.

I ain't  judging , I'm just saying.

[fj1289]

As far as the blue dot discussion -- I think the intent of the mod is more biased to feel and control vice outright braking power.  FJ stock brakes do have plenty of stopping power.  They lack (compared to more modern systems) feel and control.  The stiffer calipers should flex less (like the SS brakeline upgrade) and give better feel. 

As I recall, the different sized pistons is done to equalize the load on the pad - with equal sized pistons the leading edge of the pad sees higher braking forces. 

All that said, would still be interesting to see the results of a well done quantitative comparism test (most of us have our info from our own qualatative comparisms). 

[MyFirstNameIsPaul]

The smaller bore is on the leading cylinder of the caliper, so that one will have less force applied.  This makes sense since the leading edge will see more friction.  My '03 ZX-6R actually has separate pads for each piston, but the front pads still get worn more.  I think that equal pressure across the applied surfaces, as well as materials, may make a bigger difference than just swept area.

When I went from stock calipers to R1 calipers, there was a huge increase in the consistency of the braking, even though I retained the stock master cylinder.  The stock master cylinder makes the lever pull required considerably greater than what I prefer and I've finally gotten around to getting an FJR master cylinder (which, IIRC, is not 14 mm) to install.  It's possible the reason people are saying that they see such a large improvement with the 14 mm master cylinder is because of the reduced lever pull required.

The easiest test would be simply to install a 14 mm master cylinder on your stock calipers and see how much you like it after riding.  Then, if you decide you want further improvements, install R1 calipers and then see how you like it.

My hypothesis is that you won't like the 14 mm master cylinder on the stock calipers because there may not be enough feel and too much power, and that the 14 mm with the R1 calipers will feel much better than even stock master cylinder with stock calipers.

[racerman_27410]

 during panic stops i could never get past the light switch wheel lockup with the stock brakes

blue dots + 14mm master = i can make tire smoke come off the front wheel without it locking up.

its not about the absolute braking power .... as we all know.... power is nothing without control

no... in this case it's about "feel" and AFAIK there is no way to test "feel" mechanically..... good luck with your experiement......i personally think boiling brake fluid would be more worthwhile (although that's already been done)


LMAO Mark..... "Steve the tweaker" sounds so appropriate


KOokaloo!

[junkyardroad]

Almost there....




No mods to speak of, just a cleanup and scheduled maintenance for its mileage.  And paint. Can't wait to shoot the new paint.

[Mark Olson]

That is looking good, gonna be one clean fj.

[threejagsteve]

Steve, I would think a standard 60 mph to a full stop distance test would give you your answer.

That may wind up being about all I do - but it's difficult to exert exactly the same pressure on the lever, particularly since there's at least an hour of work to make the switch and re-bleed the system between the tests. 

I personally went from stock 86 brakes to blue pots with stock master ,then to fjr master and the effect was an increase in braking ability  at each change.

Yes, everybody does it either that way or the whole new system all at once (like I did). That was my point - nobody seems to have tried the 14mm m/c with '89+ calipers. And not only is that m/c a change from the 12mm piston diameter, but if I'm not mistaken there's also a different mechanical advantage in the lever pivot arrangement. 

have fun with your mods and whatever meds you are on that keep you up at night are giving you strange ideas and making you tweak.

No meds... my late-night brainstorms are the result of three contributing factors: long-term unemployment, too much coffee, and a snoring wife!   

All that said, would still be interesting to see the results of a well done quantitative comparism test (most of us have our info from our own qualatative comparisms).

Yes, that was my thought exactly - I went straight from a complete bone-stock '91 system (including original 18-year-old hoses) to a complete R1 system with SS lines.

during panic stops i could never get past the light switch wheel lockup with the stock brakes

blue dots + 14mm master = i can make tire smoke come off the front wheel without it locking up.

its not about the absolute braking power .... as we all know.... power is nothing without control

no... in this case it's about "feel" and AFAIK there is no way to test "feel" mechanically.....

You may well be right, Frank, I just want to make sure I'm not throwing the baby out with the bathwater.

LMAO Mark..... "Steve the tweaker" sounds so appropriate

"They all said I was mad..."