Suspension

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This should really be the starting point to making any modifications to the bike. What good is more power if you can't get it to the road, or stay on it. One nice thing about this mods is that unlike engine ones a little goes a long way.

First of all, think that the suspension tuning is near a science. Personal weigh, kind of driving and handling tastes are a major factor here. Like a guide, I weight around 72-75 kg kg, think 80 kg with all the equipment.

Motorbike suspension is basically the springs. The hydraulic controls the springs, so the 1st thing you must do is adjusting the springs to the motorcycle and personal weight.

A good guide to adjust your suspension is clicking here: Adjusting Spring sag

 

KERNITE BEARING GREASE

 

Once again I repeat that for the correct suspension work it is necessary that the headstock and the relay arms bearings make their function correctly, being greased and operate smoothly. I´m tired of repeat that the head stock and relay arm bearings must be dismounted, re-greased and properly packed and refitted is a basic work in our bikes, each 2 years or 24.000 kms.

It is extended when refitting wheel bearings: before of proceeding to fit any new bearing I open carefully the plastic cover of the bearing and always add a good quality bearing grease. Usually the bearing grease look a scarce resource at the bearing factory.

The grease oxidise with the time and the molecules break because of the friction and pressures on. Along my life I've tested various quality greases in my vehicles. But never, NEVER when I've dismounted any part the grease looked like NEW, like this KERNITE grease. In this case with 3 years and 24.000kms. At the pic you can see my Honda yoke like it was dismounted, with the grease looked like it was just spreaded. Amazing!

And at the swingarm and the dogbones was something similar: the grease was clean, without apparent degradation, green and smooth. STRONGLY RECOMMENDED

 

 FRONT SUSPENSION

 a) Springs

I have tested my FJs with 4 different springs: original equipment, Progressive Suspension, Hagon and öhlins.

Öhlins springs are too hard: it is difficult even refit the top fork caps compressing the springs, and after fitted, the fork has not movement at all. So don’t fit them unless you are planning to eat a lot of hamburgers or you weight more than 200 kg.

Between Progressive Suspension and Hagon I think Hagon are the best, because of more progressive and better feel. Progressive ones are a little harsh too.

Hagon are awesome and the bike gives total confidence with 25 cc less oil than OE stated quantities in each leg. With the 10-40 w engine oil the fork is perfectly dampened, absorbing bumps but with a perfect little dive when hard breaking. This is true for the 1100 and 1TX and 3CV FJ 1200s, but not with 3XW, 1991 on 1200: the longer travel fork of this model don't work very well with the STD Hagon springs. I would order a softer rated springs.

The original springs are not too bad, but the bike dives and bounce when hard riding. And with a few kms. they get soggy and tired.

With new harder springs you can rise 1cm max. the forks above the fork clamp, so you gain in agility. This is more necessary in the + 1988 versions, with 17 inch front wheel. On the latest 3XW this is a necessary adjustment, changing the whole bike impressively.

Particularly, I prefer the superior agility of the 16 inch versions

b) Oils

The workshop manual specifies Sae 10-30 w motor oil in the FJ 1100 forks. Use 10-40 w engine oil. Cheap than the fork oils, more resistant to degradation (so the fork inner components are more protected), more consistent damping... Excellent results!. In fact, the fork oils are cheapo oils with less additives than engine oils forced to work with more strain, more pressures and molecular degradation due to the mechanical pressures on the gear train.

 

Fork Bridge

Mingo bought it. We have tested the bikes with the bridge on and off and in a lot of situations and speeds. The best that I can say is that we can't feel any difference at all. Yeah, it looks nice

 

 

FZR 1000 87-88 Fork swap

(Work in progress)

 

My bike suspension is spot on. Front & rear sags are perfect, the bike is controllable AND comfortable, I ride with fast riders on modern bikes on weekends without complexes and only a tweak on springs let me going into closed tracks.

So It is not necessary any change. In fact the only  motivation to make this mod is the aesthetic porpoise. I look the FZR 1000 320 mm. discs, and the mod look easy at first approach because both forks look similar.

First surprise: you can not fit the FZR legs on the FJ yokes. 

The FZR wheel/spacers/speedo drive had the same dimensions as the FJ, even have the same Yamaha PN code, but there is 5 mm less material at the inner surface of the axle bosses of the FZR forks. The fork spacing is narrower by 10mm. So it would be easy to compensate with 2 0,5 mm spacers… but then neither FZR or FJ mudguard/ fork bridge fit

FJ triples have fork legs at 210mm cl to cl. FZR triples have fork legs at 200mm so if you are going to use the FZR '87-88 forks, you will need to use the yoke as well. Using the yoke is easy due to the head bearings are the same in both models and you don't have to find any problem simply fitting the complete FZR yokes into the FJ headstock.

The following problem is that the FZR forks are 3,5 cms. shorter than the FJ forks as well. And it is too much. You would have to be fiddling with other handlebars or rear height to compensate.

The measures are like follows

FJ inner legs without cap                    43.5 cm        FZR 41.5 cm

FJ fork vases from seal to axel centre 36.5 cm        FZR 35 cm

                                                 Total 80 cm                 76,5 cm

And I´ve found that inner FZR 41 mm are obsolete and near impossible to find. So a potential problem when searching for spares and clearly a BIG negative point in order to make the conversion.

The best solution is fit FJ inner tubes on FZR fork vases with a total measure of 78.5 cm

And n addition you have other problem solved: the FZR springs are too soft, so if you fit a complete FZR forks you must resprung it, with a special ordered springs. Using FJ inner tubes let you fit FJ springs, and I can keep my fabulous Hagon springs into. You can maintain even the FJ Hydraulic regulation fitting the FJ unit inside the fork. In fact the FJ damper unit is 23 cm long vs FZR 21,50

The only drawback is that FZR vases don't provide place to fit the screw that holds the FJ hydraulic unit in place when remounting the forks, so to find the hydraulic unit slot when refitting the fork caps can be a pain in the arse.

Well, this is the plan to follow. But I have to paint the FZR vases and mudguard, buy steering stem bearings and renew all the fork internals when reassemble the fork. The fork seals & bushes are the same on both FZR & FJ models, with the same Yamaha code... So like I ride near everyday day my bikes, I'm going to wait to have to change anything to do it. In the meantime, I would like to know if anyone have done it the mod and what another problems he has bought

 

REAR SUSPENSION 

 

Spring trick: The original shock fits a too soft spring, mainly with passenger and luggage. With a new OE shock and my 80 kg wearing full equipment, the spring position is ok at the OE 3rd spring position and the damping at 3, but with passenger even at 5th position was too soft. You can get more spring preload simply at this way: 

 - Adjust the remote control in the hardest position (5), disconnect it, take back the adjuster to the 1st position and connect again. Be careful that the damping adjuster is at position 3 when disconnecting and keep it there when changing the preload adjuster from 5 to 1.

But when the OE fade (all of them in all FJs because of the age) there are no solution for the poor damping: the better option is to change the shock. I have tested 4 different shocks in my bikes:

Öhlins: this is a pretty much the state of the art in shocks, but the actual difference in performance over the other listed here is questionable. The FJ fitment takes hydraulic preload, mounted in the original remote shock adjuster place.

EMC: when I fitted in my 1st 1200 it was named Quadrant. I ordered 1 cm longer than the original. Good shock, but without remote preload adjuster, and it was a pain to change the preload

White power I fitted one of them in my FZR 600. It is an excellent shock, and differently to all the other shocks, it was spot on from the crate. Transformed the FZR 600 handling. RECOMMENDED

Hagon: top notch finish and superb feeling. I ordered one with remote preload adjuster, fitted at the upper rear brake screw

  It is a fantastic shock, well dampened and good value for money. And at Hagon there are excellent professional who love their jobs. The only drawback is that the damping adjuster is via an Allen screw at the down body of the shock, but it is an easy task reaching the adjuster with the Allen key supplied.

The only drawback is the reliability: it looks like the debris from the Tenerife road pavement scratch the shock rod and then start to leak oil (this is the official Hagon explanation). The shock was repaired 3 times in a year by the excellent warranty service.

APRIL 2.012: Mingo sold his Hagon 5 years ago due to the same problem that mine, repaired in warranty too. The new owner has contacted with me recently to say me that shock continues in excellent nick. So the reliability problem that we suffered was due to the tarmac. And it is a recuurent problem in other shock brands too here in Tenerife

Betor: my friend Mingo's FJ fit one of the these. Excellent shock, and very cheap, with the damping force and spring spot on. Recommended NOTE: when the Betor faded, Mingo was looking for a dealer to repair it. Well, It is impossible. Nobody want nothing to know with repairing Betors. Definitely, a poo!. Mingo bought a Hagon too. And he suffered the same problem like me, so he changed to the OE

Take note that the shocks are totally different between FJ 1100 models, FJ 1200 86-87, FJ 3CV models and FJ 91 on, so if you find a 2nd hand shock in e-bay check the year model

 

CONCLUSION:

our bikes are experimenting a come back to their origins. Mingo, JC and myself mount OE new rear shocks with the spring trick done. Our bikes are spot on, the shock is very resistant and you can change your settings easy and fast.

My final settings to my 80 kg with equipment are:

Front fork: Hagon springs, 10-40w engine oil 25 cm3 less than recommended, near 1 cm the fork legs raised, 2nd position of 3 on springs and minimum rebound

Rear shock: OE shock with the spring mode done, position 1 on spring and 3 on rebound. Shorter rods fitted

 

SHORTER REAR SHOCK TIE-RODS FITTED

On post 88 FJ models you can shorten the rear rods legs, upping the rear of the bike and gaining in agility. This is a necessity if you fit modern rim sizes because the short total diameter of the wheel with modern tyres.

It is an  easy task.

Check the centre bearing fitted in the central rod assy: if it is in bad shape, change it. It is an expensive bearing: To extract it, make an extractor with 1 stud, nut and shim and 2 vases, 14 & 17 mm, as you can see at the photos.