SoCal Fix-Up: The Next Generation

[threejagsteve]

The Thunderace swingarm does not have a shorter wheelbase than stock. 

Well, that contradicts what's on the FJmods site: http://www.fjmods.btinternet.co.uk/

And if it's so not a good idea, why did YOU do it?

And if I have the complete FZR1000 rear wheel - sprocket carrier, spacers and all - what difference does it make that the T-Ace units are different? I'd only be using the T-Ace arm, and perhaps the axle if the FZR axle isn't long enough.

And BTW, the correct tire size for a YZF600 rim is a 160... just because you can get a 170 on doesn't make it right.

[andyb]

And BTW, the correct tire size for a YZF600 rim is a 160... just because you can get a 170 on doesn't make it right.

A 160/60 is usually used on 4.5 and 5.0" wheels.
A 170/60 is used on 5.0 and 5.5" wheels.
A 180/55 is used on 5.5 and 6.0" wheels.

This is from the Pirelli spec sheets.

[derbybrit1]

>>Well, that contradicts what's on the FJmods site: http://www.fjmods.btinternet.co.uk/

That information is incorrect.  Again, I used stock sprockets and chain.  Stock wheelbase is preserved.  You can't believe everything you read.  Sometimes you have to do your own homework.

>>And if it's so not a good idea, why did YOU do it?

I used the Thunderace swingarm with the Thunderace wheel.  And it turned out great.  Just ask Pat Conlon or Gary Mastro, who have Ace conversions that I built.  Using the Ace wheel, not an FZR1000 wheel as you have. 

And a swingarm is not just a swingarm.  There is such a thing as wheel offset and swingarm width, front and rear.  The FZR is not the same as the Ace.  And countershaft sprocket alignment is an issue as well.

Anybody tell you how using a 180 on the 5.5" wheel is so close to the chain that you have to be careful what tire you select? 

I'll tell you a quick story.  Brian Hunt, a really good guy from the Pacific NW, met up with us at a rally a few years ago.  He had done some kind of FZR wheel conversion, and he had a ton of room between his tire and chain.  I referred him to my Ace conversion, where there was almost zero tire clearance.  It took some discussion before he understood that the different swingarm and sprocket carrier offset allowed him good chain alignment, but his wheel was probably 1/2" off-center.  I built a measurement jig to insure my wheel and sprocket were perfectly centered, so that was the end of the technical discussion.  In practical riding terms, his setup appeared to work just fine.  I didn't ask him how it worked flat-out in 5th gear.

A YZF600 wheel and a new set of dogbones is a good starting point.  No chain or tire issues.  You can do that in the $100 price range easily.  If that inflames your the modifier virus, then you will know which path to take. 

[tqmx1]

Mark, Just looking at them the thunderace arm sure looks a lot like a G1 FZ1 arm.

[racerman_27410]

I saw this posted earlier in this thread by racerman_27410 and thought it appropriate to comment:

"I have a 1349cc engine  (stock valve sizes) and i'm getting 162 at the rear wheel with 115 lb ft of torque on pump gas. 10.25 compression"

I promised my old Kookaloo buddy Frank that my 2 cylinder Aprilia would have more horsepower than his mighty Brutus.  And I have made good on that promise.  Frank's mountain motor makes 162rwhp, on what I would guess is a Dynojet 250i dynamometer.  That is equal to or better than all the current Japanese I-4 liter bikes available in 2009.  A worthy accomplishment for the FJ.

My Aprilia makes 181rwhp on a Factory Pro dyno.  The correction factor from Factory Pro to Dynojet is between 1.15 and 1.20 in that horsepower range, which conservatively yields 208 Dynojet rwhp with 11.4 psi of boost.  On pump gas.  Now THAT is Kookaloo!

Still have some tuning to do, but working toward a run at The Texas Mile this Spring.  And if all things go well, we might make it to the Maxton Mile as well.  All will depend on whether the motor can hold together or not.

Damn those are some serious numbers on that I talian bike... of course you are doing some major ramming if the charge into the cylinders WITH A SUPERCHARGER !!!!!!! 


and BTW have you been taking assatall pills?    You have gotten so skinny it looks like you're wearing someone else's pants!  (explains the lighter springs you are now using  LOL

KOokaloo!

[higbonzo]

Anybody tell you how using a 180 on the 5.5" wheel is so close to the chain that you have to be careful what tire you select?  

I'll tell you a quick story.  Brian Hunt, a really good guy from the Pacific NW, met up with us at a rally a few years ago.  He had done some kind of FZR wheel conversion, and he had a ton of room between his tire and chain.  I referred him to my Ace conversion, where there was almost zero tire clearance.  It took some discussion before he understood that the different swingarm and sprocket carrier offset allowed him good chain alignment, but his wheel was probably 1/2" off-center.  I built a measurement jig to insure my wheel and sprocket were perfectly centered, so that was the end of the technical discussion.  In practical riding terms, his setup appeared to work just fine.  I didn't ask him how it worked flat-out in 5th gear.

This is exactly why I didn't attempt to do this set up via the FJ Mod page.  I had a professional machinist and motorcycle gurus (Poway Motorcycles) set mine up.  It is a complicated set up, but when done properly the FZR1000 rim in the stock FJ swingarm is a tremendous performance and ride improvement over the stock set up.  And I can tell you that my bike will run out at over 140 mph very nicely, as well as travel down the interstate at any rate of speed very comfortably and securely planted to the road.  Now, If I can just get the front forks set up to handle stopping and turning of the beast more efficiently I would be happy all the way around.  Hint, Looking for another Guru, someone who knows a bit about the YZF750 USD fork set up, for a little help.  

Anyways, it is always best to have all your ducks in a row before you start any modification.

Later.....

[derbybrit1]

Marsh also has a FZR1000 wheel conversion.  If properly done, they are just as good as an Ace wheel.

I think the writeup about YZF750 forks I posted on Barry's website is pretty complete, with pictures. 

If I had to do it over again, I might have put new posts on the lower triple clamp instead of putting a bigger block on the steering neck.  I think the decision came down to which method had best strength and did not require welding.

Let me know if you have any questions.

[racerman_27410]

The Thunderace swingarm does not have a shorter wheelbase than stock. 

Well, that contradicts what's on the FJmods site: http://www.fjmods.btinternet.co.uk/

And if it's so not a good idea, why did YOU do it?

And if I have the complete FZR1000 rear wheel - sprocket carrier, spacers and all - what difference does it make that the T-Ace units are different? I'd only be using the T-Ace arm, and perhaps the axle if the FZR axle isn't long enough.

And BTW, the correct tire size for a YZF600 rim is a 160... just because you can get a 170 on doesn't make it right.

Steve

I think maybe you should take task....  go digging thru a motorcycle junkyard with a tape measure and micrometer so you can come up with something all on your own....you know.... a mod that NO ONE has ever done before.... "perfect" mods that suit your idea of what your FJ should be!.... that would give you a little more street cred when debating a "pioneering modifier" .  right now you got a bunch of ideas..... Rittner has the facts AND the street cred to back up his statements.


Marc has done his homework.... he has tried mods that didnt work and found some others that worked very well... i really dont think he has any reason to BS you .....JMO but actually developing a clean functional mod for a FJ is a lot harder than dreaming while clickity clacking some keys on a computer keyboard

KOokaloo!

[Marsh White]

Rittner has the facts AND the street cred to back up his statements.

KOokaloo!

FYI: So does Frank.  He was the 1st one to do the FZ1 mods to an FJ - he (actually his sister I believe) also invented the word Kookaloo...

This is Frank (racerman_27410 - in case you don't know): http://www.btinternet.com/~fj1200mods/FrankMoore/FrankMoore.htm

[racerman_27410]

FYI: So does Frank.  He was the 1st one to do the FZ1 mods to an FJ - he (actually his sister I believe) also invented the word Kookaloo...

This is Frank (racerman_27410 - in case you don't know): http://www.btinternet.com/~fj1200mods/FrankMoore/FrankMoore.htm

LMAO....my little sis may have coined the term "Kookaloo"  but the feeling has existed since the dawn of the wheel and the first person to roll off the top of a steep hill   


KOokalooooooooooooooooooooooooooooooooooooooooooooooooooooooo!

[higbonzo]

Marsh also has a FZR1000 wheel conversion.  If properly done, they are just as good as an Ace wheel.

I think the writeup about YZF750 forks I posted on Barry's website is pretty complete, with pictures. 

If I had to do it over again, I might have put new posts on the lower triple clamp instead of putting a bigger block on the steering neck.  I think the decision came down to which method had best strength and did not require welding.

Let me know if you have any questions.

Thanks.  I am sure I will.  I was thinking it may be cleaner to cut the tabs and re-weld them in their new position.  I'm not much of a welder, although I have the welder to do the job.  But, I think by the time I bought the gas, and set it up with new line, I could have someone weld the tabs back on for me. 

I will certainly be fallowing up with you on the YZF set up.  Right now I have my hands full changing out the fuel pump in my wife's 02 firebird.  I swear the GM designers' must plan their designs around how they can make the service departments some $.  It takes about 5 minutes to switch out the pump and 5 hours to get the tank out and back in again.  It is crazy..

Later.....

[threejagsteve]

I'll tell you a quick story.  Brian Hunt, a really good guy from the Pacific NW, met up with us at a rally a few years ago.  He had done some kind of FZR wheel conversion, and he had a ton of room between his tire and chain.  I referred him to my Ace conversion, where there was almost zero tire clearance.  It took some discussion before he understood that the different swingarm and sprocket carrier offset allowed him good chain alignment, but his wheel was probably 1/2" off-center.  I built a measurement jig to insure my wheel and sprocket were perfectly centered, so that was the end of the technical discussion.  In practical riding terms, his setup appeared to work just fine.  I didn't ask him how it worked flat-out in 5th gear.

Now that IS a scary story! LOL He actually hadn't noticed that the wheel was off-center to the rest of the bike?

Marc, it was actually your detailed writeup of the T-Ace conversion that convinced me of its feasibility.

Though I haven't done much to my FJ yet, I have a good bit of experience modifying other, mostly 4-wheeled, stuff. And no, I don't just mean bolt-ons. Once upon a time, I had a fair bit of "street cred" as they call it these days for being the first anyone knew of on the Gulf Coast to put a 351C in a '67 Mustang. That was in '73. I'm not around here much on Saturdays because Saturday is Jag day... I'm currently turning a '66 3.8S into a rat rod.

Anyway, I'm at least aware of all the issues you raised regarding the T-Ace arm, even if I haven't engineered solutions yet.

Yes, I've been throwing out a bunch of ideas, looking for comments and feedback. The online equivalent of what we used to call bench racing.  

And yes, Marsh, I know "who" Frank is, and Frank is right... Now I should SFU until I've accomplished something worth posting.

And finally, thanks to everyone who's taken the time to contribute comments, constructive criticism, and ideas to this discussion.

[derbybrit1]

I guess there is no reason to toot my own horn if my buds do it for me.  Thanks, guys.

Somebody mentioned that an FZ1 arm looks a lot like an Ace arm.  YES, it is very similar.  Same extrusion.  But it is longer, and the wheel is different, and I think it is little wider at the rear of the arm as well.  But as Frank demonstrated, a perfectly fine and easily aligned conversion.  Extra length wheelbase a problem?  I say no.

Look at the new BMW K1300's.  They have a 62" wheelbase IIRC.  That is a TRAIN!  But I have heard few complaints.  And don't be surprised when that Beemer sucks the headlight right out of an FJ when it goes burning by...straights or corners.  Modern technology is wonderful.  But still no substitute for skill, experience, and balls.  That's a page right out of Frank's playbook.

[racerman_27410]

it might be a little longer than stock but its not like the rear tire is hanging out the back like a main street squid either.... notice i have the wheel at its most rearward position with the 18/ 38 sprockets..... but.... i can swap gearing to 18/39 ,18/41, 17/41 and 17/44  without having to modify the chain.


gratuitus ass shot .... this is the part the wannabe's see when the light turns green     




it hasnt stopped me from going around even the tightest,decreasing radius uphill corners either




Here is a little taste of the kind of roads we have around here.....  This is  "green"..... East Coast style !





damn i love some riding shots.......


makes me wanna KOOKALOO!

[tqmx1]

Frank, If you have any intrest in it I installed a 02 or later R1 wheel under the back of my FZ1. It's not that big of a job. The drive side  remains the same and all the mods are made in the brake side.

Kim