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FJ Dragbike Project

Started by fj1289, March 22, 2010, 12:39:45 AM

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the fan

Not sure. I have looked at both machines several time, but drag racing has never been a big interest for me. World Wide Bearings sponsors a god friend of mine so we usually meet Scott Valetti at the WWB booth for lunch.

I have known Scott for several years via my buddy Rob. Scott is the one who hooked Rob up with Dave at WWB.

I thought it was funny when someone asked me why I was eating lunch with the owner of AMA dragbike, and I had no clue who he was talking about...

Do you spend time over at www.dragbike.com?

the fan

Just looked at a few pics, and here is one of the 1000 with the forks reversed. Looks like he is only running 1 rotor.

ren-dog

Quote from: fj1289 on March 23, 2010, 02:19:23 AM

Damn that's looking good.
If building it is half the fun, then it's gunna be one hell of a ten second ride. :wacko1:
There's a huge amount of adjustment for that rear wheel.
That much adjustment would also help trim the rear spring rate.



That linkage is a work of art. Wish I was that bloody clever.
Where's the NOx gunna go ???
I remember the world before Workplace Health & Safety.
ren-dog

andyb

If that thing does what I'm guessing, it's not gonna be a 10 second ride....

fj1289

About the lockup – I talked to Orient Express about a month ago.  Late last year they sold the last FJ lockup they had.  I think they were made by MRE, but are no longer making them.  It seems like the FJ is the king of the "that used to be made for it but is no longer available" compared to all the other bikes.  For others, it is still made for the old school Kaw's and Suzi's, or it was never made for most Hondas or Yamahas!

Getting a stock wheel base down to 10.05 is no easy feat, even with a pumped up motor.  Do you have any of your time slips?  It'd be interesting to see the 60 and the 330 times and the mph.

I've only heard good things relayed about Ken Stotz.  I've got a couple of magazine articles on that bike I flip through from time to time to help get new ideas.  This bike will go through a few iterations getting to the "final" setup.  I'm intentionally not doing some things (like reversing the fork legs, putting the battery in the fairing, etc) until I've got the basics sorted and it is running consistently.  I have to stop myself from trying to "improve" on too many things or I'll never get the thing finished and on the track!  And this is the first place I've lived where winter is serious – so that is the built in time to do future mods!  The forks are early R1 forks (a 99 I think) and have been internally lowered.  They are pretty freaking stiff now – they have some travel left, but you won't use much of it unless it's coming down off a gangster wheelie.  Really not planning to try that out though!

I'm over on dragbike.com occasionally.  I spend more time on psychobike.com.  Dragbike.com is great for getting solid info from guys that have been in the game forever – it is mostly the wheelie bar crowd.  Scott is good people – always very responsive when I've had an organizational question, and constantly playing the balancing act between racers, sponsors, and fans that is required to keep an organization like that going and growing.  Psychobike.com is more entertaining and more of the no-bar street tire scene.  Good place to find info on later model bikes and the mods being done to them now.  I've tried to mix the best of both – we'll see if it works or not. 

For not being interested in drag racing, you sure do it a lot – at the start of every road race!!!  Everyone you out drag to turn one is one less person you have to pass later!

I'm hoping for a bit quicker than 10's.  I went big on two things – the clutch and the top end of the engine.  When I was just getting really well hooked about two years ago, I bought a bunch of parts off psychobike.  By this time the 1200's tranny was about done with the abuse and I wanted more power!  The parts included a ported big valve head, cams, a bigblock with 1380 pistons, crank with carrillo rods, the bored cases, and an undercut trans.  I hastily bolted it all back together and tried running it as it was.  Attempt number one had the cams out of time (intake off by 1 tooth and exhaust by 2!  Wonder it ran at all and didn't break anything either!) and the piston rings not sealing well.  Even after I got the cams timed properly it continued to push a lot of oil out the breather and base gasket.  I eventually put another used 1314 kit on the same lower end and a fresh head on it.  That was the combo I got down to 10.79 at Bandimere.  That was also the day I spun the #4 rod bearing.  Noticed the bike lacked pull at the top of the last run and the mph was down considerably.  The damage wasn't bad (especially since I didn't try running it anymore!) and was repairable at reasonable cost.  It was at that point I decided to press forward full speed with a dedicated dragbike and put the 89 back on the road full time again!  I had a lot of pressure to do a Busa.  Almost pulled trigger on one, but decided at that time that I really didn't WANT a Busa no matter how smart a decision it may be – it had to be an FJ.  But, I'd build the FJ with all the current mods and tricks and go fast ideas – and shouldn't have to make any excuses for it's age.  It may not be quicker than a Busa, 14, GSXR, CBR RR, that's modded similarly, but it'll be close enough to bite 'em if they aren't careful!     



doright1

10.79 is still more than respectable, especially considering that Bandimere is at 5800' of elevation!
Bob P.
'84 FJ1100
Greeley, CO

Don't steal.  The government hates competition.

thors ax

Quote from: doright1 on March 25, 2010, 08:59:56 AM
10.79 is still more than respectable, especially considering that Bandimere is at 5800' of elevation!
I agree, that's gotta be darn close to a flat 10 down at altitude!  I'll try to hunt up some slips I may have scanned into the computer at the time, as most of the tracks I went to used thermal-fax type printouts.  I too believe you will be in the 9's with the swingarm, and with lots less drama (please!).  What are you running for carbs then?  I'm on 44PHH Mikuni Radial Slides with short stacks.

Cheers

Scott J
85 FJ1389 - Thor
92 FJ1200 - 'minime' for now


andyb

No spoilers about your combination, fj1289?  I'll keep my yap shut until you spill the beans on it :empathy3:

However I know exactly where the head that was used for that run is going to be put... hopefully it sees some good numbers!!  At some point I'll post some of my build pictures, but not the ugly ones (which doesn't leave much, I'm not much of a mechanic) and start my own bloody thread about racing.  We could even get a subforum for the three or four of us who like to dragrace :P


As for Mr. Stotz, when he was at the track he showed me his DA setup and I ended up spending a fair amount of time annoying him...er.. helping him (read:  playing tool bitch) while he was troubleshooting a nasty leak that only showed up over 6psi on the RR.  Super nice guy, fantastic rider, and a very determined individual.  Sadly the track was junk for a >400hp bike that day, and he ended up by giving up on tuning because of the track prep after only 3 runs.  Ran a flat 9.0 after shutting off at half track as I remember though... scary, scary machine.

fj1289

Not much progress lately - working on subframe, undertail, and mounting the electronics.

This past week has been a complete nut-crusher at work.  A couple of 15 hour days ( I also have a 1 hour commute each way) and none less than 12 hours - the whole time working like a scared rat.  Some progress last weekend, none this week.  Supposed to be out of town this coming week -- TBD now. 

The old combo was a 1314 top end (that needed new rings), a ported big valve head, mild cams (still shim over bucket), and Keihin FCRs (39mm).  Really liked that combo - especially for a street bike.  Going to be hard to go back to a stock motor for the street bike!

I thought I'd already mentioned the combo for the dragbike - must have been another thread.  The dragbike build is based around some used parts I bought a couple years ago, but have been completely reworked.  The aftermarket big block has been taken out to 85mm (1447 cc's) with custom JE pistons (weigh the same as smaller 1314 pistons!), refurbished Carillo H-beam rods, a race ported big valve head, shim under bucket Web cams, and 40mm Lectrons.  Also running a stock crank that's been balanced (NOT lightened) and nitrided.  Paul Gast (did the pistons and head work) said it should be a reliable bracket racer that'll only need frequent oil changes - shouldn't even need freshening up after a season!

Just need to finish up the chassis and build the engine (most of that effort will entail multiple times putting things together, measure clearances, disassemble, adjust, reassemble, recheck, disassemble and prep for final assembly (if it's all right at that point)!   

Tracks here are opening now -- I'm ready to hit it -- got to get finished!


fjdragbike

just joined the forum  :drinks:  cheers
fj1289,
Is that spider pipe your using a custom made or from a gs1100?
Im building an fj dragbike and cant for the life of me find a
sidewinder or spider pipe for this bike.I read a thread suggesting
that the gs 1100/1150 pipe will work with some fanagling.
thanks,Steve

Pat Conlon

Quote from: fj1289 on April 02, 2010, 10:50:44 PM

..... Also running a stock crank that's been balanced (NOT lightened) and nitrided...... 


What's your reasoning on not lightening your crank? Better control? Durability?

Great project! Very cool to see a bro. wave the FJ flag in the face of the powerful Suzuki's and Kawasaki's
Keep us informed of your progress and results....Cheers.
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

fj1289

Quote from: fjdragbike on April 06, 2010, 06:27:36 PM
just joined the forum  :drinks:  cheers
fj1289,
Is that spider pipe your using a custom made or from a gs1100?
Im building an fj dragbike and cant for the life of me find a
sidewinder or spider pipe for this bike.I read a thread suggesting
that the gs 1100/1150 pipe will work with some fanagling.
thanks,Steve

Steve,
It's an old Murray pipe for the FJ.  I looked for more than two years for a sidewinder for an FJ.  Bought a whole bike for a V&H sidewinder and then a week later got offered the Murray from a guy on Psychobike.com. 

A few ideas - I've heard a sidewinder for a V&H sidewinder for a KZ fits the chassis better but the spigots are wrong -- maybe could cut those off and fabricate stubs for the head and mount the header in the stubs using quick disconnect springs. 

The GS1100/1150 pipe fits the head - but the tubes do have to be spread out a bit - spacing between 1 & 2 and 3 & 4 are good, but 2 & 3 are too close together for the FJ - so you have to spread everything out a bit.  Also have to elongate the holes in the flanges since the FJ exhaust studs a slightly farther apart than the GS studs.  I do have a V&H sidewinder header for the GS, but don't have the megaphone any more.  PM me if you are interested in it - I've had it mounted up, but have not run it.  It is ceramic coated silver and is in good shape - the divider plane in the collector has come loose at one of the tack welds - easy repair. 

Another option is to have a custom header made.  Anyone that does custom car headers should be able to hook you up.  Will be $$$ though.   

I do have the V&H FJ sidewinder too if you are interested, but I need to check with another member here first since we've discussed it already. 

What are your plans for your dragbike?  Street tire or slick?  Bars or no bars?  Full frame?  Stock frame?  Shock or strut?  Engine specs?  Bracket bike?  ET?  Grudge?  "Just" TNT? 

There's a small thread on the oldschool forum on psychobike on FJ's.  Not a lot there yet, but a couple of people are putting together FJ's for the strip. 

Good luck and keep up posted on your progress and results!

Chris

fj1289

Quote from: Pat Conlon on April 08, 2010, 01:06:12 PM
What's your reasoning on not lightening your crank? Better control? Durability?

Great project! Very cool to see a bro. wave the FJ flag in the face of the powerful Suzuki's and Kawasaki's
Keep us informed of your progress and results....Cheers.

Thanks Pat!  Getting anxious to get it done!  It should run pretty strong - the time slips have the final say though!

On not lightening the crank - I've been told from a few different sources that FJ cranks are prone to breaking in dragstrip use if they've been lightened.  I haven't been able to find out the exact cause of this -- the sudden shock at launch?  higher RPMs?  Hard acceleration followed by sudden deceleration?  Heavier pistons?  No matter the cause, I've chosen to heed the warnings!

Chris

andyb

The other rationale to not lighten the crank is to retain as much inertia within the rotating assembly as possible.  Helps keeps the revs up on shifts, and is "free" energy at the launch.


fj1289

Progress has been slow, but have a few updates.

Sprayed the tank and fairing - both need a little sanding and another shot of clear.  Used Rustoleum Sunrise Red (7762) from previous posts on the list.  I found Duplicolor Silver Charcoal to be a reasonably close match for the silver.  It is a little too "bright", but will work for my purposes.  The gloss is good on the Sunrise Red, but not the Charcoal Silver, so I've oversprayed with Rustoleum Crystal Clear.  I've gotten the best results onthe clear by spraying a "wet" coat - went a little heavy with it on the tank and have some runs to sand out.  Went a little light on the fairing and didn't get the same gloss.





Trimmed some tabs and lugs at the rear of the subframe and cut down the trail light for more tire clearance when the bike squats on launch.  Also fabbed an undertail – “version 1.0” is made from several pieces of thin (.025”) AL sheets from the hardware store.  I’ll redo it later from a solid piece of .05 or .063 sheet AL (like the tiger tails available for late model bikes). 







About half way through the wiring.  Most of the wires are run, but still need wire in the shift system and data acquisition, rerun a couple wires, trim it all to final length and bundle it up neatly. 





I finally have everything on hand to start on the engine!  Just have to clear off the kitchen table first!  (That’s where I’ve been doing my plastic “welding” to repair a lot of these panels)