Draggin' Your FJ With 'Hot' Rod Mumford
Seems like the FJ still has a hardened following in the drag racing world. Rodney Mumford mailed me these pictures of his beauties, together with this every FJer's guide to dragrace preppin' . Rod's words are in mauve.
THE STRIP BIKE - On the car tire bike I have spent a lot of time and money. The first thing I had to do when I got the bike was redo most of the welds and some of the bars. The welds were nasty and some of the bars were in places that they didn't need to be. After that the frame went to the powder coat shop, this process is a very good idea and well worth the money. It lasts ten times longer than any paint. While I was building the motor I sent the body out to be painted. Red and white base coat and clear coat urethane paint.
The motor is a 1400cc (1380) Wiseco Kit (no longer available from Wiseco) Yamaha FJ, starting out a stock '86 1200cc motor. Bored the stock jugs (since the aftermarket Big Block is discontinued). The stock jugs work just fine for this kit, if you plug the air holes in the bottom. If you don't, they leak oil. Then you must O-ring the top of the cylinders to keep the head gasket from blowing out.
Rod's Street FJ
One for the Strip
The Quick Seat !
The head has a stage three port job that flows 130 CFMS (stock they flow 85 CFMS). Then buy the majorly expensive camshafts. Try to buy these used as they cost $650.00 new. With slotted cam gear, bronze guides, all new stainless steel valves (oversize intake), .500 lift springs and shims under buckets.......you're ready to fly !!
Next send the trans out to get it under cut. This will also fix the second gear problem. While you are in the bottom end you should take out the oil blow off valve that is in the main oil passage way. Take it apart and put two washers in on top of the plunger to increase the spring pressure. This will increase the oil pressure. Then put an oil restrictor in the top cases so that all the oil doesn't go to the top. Before you put the cases together you must install heavy duty studs for the cylinders. Then you are ready to assemble the bottom end.
After you assemble your motor you should always degree your cams before you fire it up. This is even more important, as the higher compression you are running, the closer the piston to valve clearance will be. The centreline is usually 110 degrees.
When assembling the motor, leave the alternator and starter off and use a block-off plate. On the opposite side to the pick-ups, you tap the crank and put a starter nut for a remote starter.
Next step is to make the motor work in a car tire bike. This is a whole different world !
You need a 3 inch offset output sprocket. To run this you have to cut a hole in the side cover for the sprocket to go through and the sprocket will now be on the outside of the cover. On the inside of the sprocket (on the gear side), there will be a bearing that rides off of the plate on the side of the motor, then bolts to the frame to support the output shaft and keeps the motor supported from twisting. This gets the chain past the oversize rear tire. You now have to hook up this huge motor you now have. I run a 16 tooth front and 45 tooth rear sprocket.
After you have the motor all bolted in and chain on, you have to wire it. I run all Dyna electronics, they have never let me down. I recently installed a Dyna 2000 box. Very nice piece. It comes with a new pick -up and does away with the stock ignition box everyone hates. To complete the installation use the grey Dyna coils specially made for the kit. It's a very easy installation, the first one only took me 45 minutes.
THE STREET BIKE - Now the street bike was not so difficult. It is mostly stock besides the 1314cc Wiseco kit. It has a stock head, no port work, stock cams and stock carbs. After that the only other thing I did was fit the slick and wheelie bars. The bike runs 10.30's at 126mph. Not bad.
IF YOU HAVE ANY QUESTIONS JUST E-MAIL ME AT:- email@example.com
TOO FAST IS NEVER ENOUGH. SEE YA . THE HOT ROD
Quaker City Dragbike Champion 1999 - Rodney Mumford
Check out Rodney's website at :- http://www.prochassiecycle.com/
RODNEY'S CV -
MY NAME IS RODNEY MUMFORD ,I HAVE BEEN RIDING FOR TEN YEARS AND RACING FOR SEVEN. I STARTED OUT RIDING A 700 HONDA SHADOW. THEN SOLD THAT TO BUY THE YAMAHA FJ 1200. I STARTED TO RIDE IT TO THE TRACK AND FROM THERE IT JUST GOT WAY OUT OF HAND. I BOUGHT THE CAR TIRE FJ SHOWN IN PICTURE AND BUILT THE BIG MOTOR AND SO ON .
I ALSO HAVE A CAR TIRE KAWASAKI WITH A 1500 CC KZ MOTOR WITH J MODLE HEAD. I ALSO BUILT THE TRAILER IN THE PICTURE OUT OF A BOX FROM SEMI. NOT BAD EH!
I AM A CNC MACHINIST BY TRADE, WHICH HELPS TO MAKE SOME OF MY OWN PARTS AND SAVES ON THE WALLET.
I HAVE BEEN DOING THIS FROM MY TENTH GRADE YEAR IN HIGH SCHOOL, BY TAKING IT IN VO-TECH.
I AM BUILDING A STREET BIKE RIGHT NOW TO RIDE AROUND TOWN. EXACTLY LIKE THE 86 FJ IN THE PICTURE.
IF ANY ONE HAS ANY BUILD UPS ON AN FJ OF THEIR OWN, I WOULD LOVE TO HEAR THEM AT:- firstname.lastname@example.org
I would like to thank Rodney for taking the time to write down his experiences and allowing me to feature his bikes at the FJ Mods site.
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