FJ Racer; Building Page 5

Misc;

Something I knocked up was a support that acts just like a side stand. Because of the need to remove both centre and side stand when you step off the bike it difficult to hold the bike up and fit a paddock stand by onesself, so I fabricated a stand that simply located on the same location as the side stand and can be fitted whilst still sat on the bike.

Because of the removal of the footrest hangers I had the swing arm bolt reduced by 30 mm; this made it flush fitting to the bare frame.

To aid crash protection I fitted some R&G crash bungs. These are massive bits of plastic that are designed to fit the XJR and happen to fit the FJ perfectly. I was unhappy about using the Renntec engine crash bars because of ground clearance and weight (not a problem on the road!)

I set up the gearing to a standard FJ1100 gearing, 17t front and 41t rear. Fitted a DID racing chain which is lighter than the road ZVM chains and equally as strong.

Mushrooms fitted for protection

 I road tested the bike on the road to set up the suspension and to bed the new piston and rings in. After 400 miles I placed it on the Dyno.

Now it’s a matter of putting the FJ Racer on the track in a race. The class it can run in is called ‘Forgotten Era’. This allows any road bike that was manufactured before 1989, mainly racing is Yamaha Exup and Suzuki GSXR1100/750’s.

I know it’s a tall order to put the FJ sports tourer up against them but then again it might embarrass a few, so I’ll let you know how I get on towards the end of the year.

It’s all very well building a bike but it’s a different matter actually racing it. Things that you have done to the bike may look good but can perform poorly (look over function).

With the FJ Racer I’ve done every thing for performance, even the frame has its original flaky silver paint, to be honest it looks a little rough, perhaps if I do well this year I’ll clean it up over the winter.

Before completing at the first race at Anglesey I took the ‘Fudge’ to Mallory for a track day. I was pleased with the bike, it went well and I was managing to consistantly lap at around 2”03. The guy next to me (ex racer) was on a slick shod Yamaha R1 2001 model and we clocked him doing 2”04.

The power comes in really good from 6,000 revs and where a normal FJ motor tails off power at 8,500, this motor keeps pulling well past the red line at over 9,500. Accelerating from Dunlop Esses the FJ was lifting the front wheel at max revs in third gear at a speed of over 110mph, not bad for a 22 year old bike!

The handling was impressive to, no wobbles or weaves, I increased the rear rebound on the Penske rear shock from stock setting, it was a shame that the front has no form a damping adjustment as this could do with firming up, I will try thicker 15 weight oil at a later date.

The tyres were 120/70ZR17 and 180/55ZR17 Pirelli Dragon Corse (Race compound) these are not the latest spec tyres but was convinced by being £50 a pair cheaper. The grip takes some getting use to as you can carry a lot of corner speed and accelerate hard whilst banked over compared to say a fast road tyre like the Bridgestone 012SS.

'Doc' going through the Bus Stop at Mallory

Prior to the race I made a few changes to the FJ Racer. First was to remove the Gilles handle bars and replace them with a modified straight tube handlebar, reason was, simply, the handle bars would touch the tank slightly and the tube bars are lighter and neater.

The biggest problem with the FJ, compared to the FZR’s I’m racing against, is its weight. I worked out that a standard GSXR rear wheel was a massive 3kg lighter than the Exup wheel I have fitted, (this shows you how bikes over the last few year have developed). While this was being fitted I used the smaller OE Gixer rear brake disc and I adapted a 916 rear brake caliper to fit (this is half the size of the FJ item).

I have had problems with the exhaust decking out so, to sort this out, I attacked it from both sides. First I replaced the rear Penske spring with the next weight up (19kg) as it mainly happened in the dip through Schools corner at Anglesey. Secondly I fitted an Akrapovic 4-2-1 exhaust system that was originally designed for the XJR, this was also 3kg lighter that the old Devil 4-1 system. This allows the exit pipe to fit tighter into the chassis, to the point that I had to cut off the centre stand location mounts.

With all these lightening mods, I have got about 36kg off the Racer compare to the standard FJ1100 (252kg wet), this works out about 5 stone.

I was having problem with the seat height due to the bike being so jacked up for ground clearance, the solution was to fit an old 916 seat onto the FJ base (over the winter I will get it professionally fitted so it looks better). This flatter seat also helps when I’m hanging off the bike whilst cornering.

Finally I took it over to Tim Blakemore for a horse power check on his Dyno as last time I did this it was showing 117bhp and this was on a tight 400 mile only (new rings fitted) engine. That time I was told to up the main jets and lean the bottom end off which I had done by increasing the main jets to 120 and lower the needle to the lowest position. With this and the new exhaust system the motor kicked out an impressive 132bhp at the back wheel. Yes you have read that right!

 Tim told me that an early R1 on this Dyno produces between 125 to 130 hp so not bad for a 22 year old engine. Also he mentioned it was still too lean on max revs and I should increase the main jets again and this might yield another 4 hp, so I fitted 125 main jets.