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Lets face it, the FJ has a monster engine. The FJ power is so smooth and tractable that some don't realize how fast they can be until they learn to wind it out properly. As with anything though, sometimes you want more.


Dyna Coils

I read that the original coils are weak, and that a hotter ignition system was better if you tune up your FJ. So I fitted Dyna Coils with HT leads in my 1100. The only I can say is I could not feel any difference at all. It seems to be than hotter spark is better suited for elderly, oily motors. Well, my FJ 1100 did 165.000 km and when I checked the cylinder compression it was between tolerances. (When is old an FJ engine?). So I think fitting the coils only is a good idea if your FJ burns any oil.

Aftermarket coils

I bought them at eBay and I didn't spend too much money, so I can say that these are shit: the bike stalls like a bronco bull between 1000 to 2000 rpm. Exactly the same that my FJ 1100 did when I fitted Dyna Coils without the ignition advancer. The ignition curve vary abruptly at that range and the carbs can't cope with a hotter spark without an advancer that smooth the ignition.

I can't recommend it. If you have a problem with your OE coils, look for a 2nd hand ones at eBay like a cheap alternative, unless you want to start to play with ignition and carb settings, like myself when I owned my 1100... and I remember that at the consultory section I have a question about this too. Read it. It is the same problem.  


OE COILS: the best choice

(Thanks to Randy, expert FJ owner, mechanical, tuner & product developer for FJs from RPM RACING)

The coils have them same values between O.E. and aftermarket. The difference is at the plugs wires. The aftermarket utilizes carbon core automotive style spark plug wires with a connection at each end; coil & plug. The wire ends are then crimped on the soft wire and are a weak connection point. They then use the spark plug wire as the resistance of the secondary ignition circuit.

The stock coil uses a stainless steel solid core secondary wire. The wire, while replaceable at the coil, is sealed and does not have a failure point at the coil base connection as there is a needle that pierces over an 1" into the solid core of the wire. The spark plug boot then screws onto the end of the spark plug wire for another positive connection. The spark plug boot is bake-o-lite and is not susceptible to breakdown due to hear.

If you ensure there is the proper voltage source at the stock coils, you cannot generate any more spark voltage, as long as the coils test within the specifications of the service manual.


Coils relay installation to improve the ignition, getting a hotter spark at the plugs


Like Randy said, you're not going to get a hotter spark with new coils, but anyway you CAN improve your ignition system: using a relay to feed system voltage to the coils directly (using a fatter wire), avoiding voltage drops elsewhere in the system.

The power to the coils runs thru the main (key) switch, and a bunch of connectors. Each connection/switch will have some resistance and an associated voltage drop across this resistance. These voltage drops add up and, in consequence, the device being fed this power gets less than battery voltage..... The relays eliminate the resistive connections and each device fed thusly will get nearly-full battery voltage. 

Using a tester I checked that the coils were feed by only 10 v. With a relay I've gained 2 v. More voltage in means more voltage out from the coils: better and hotter sparks.

I fitted the relay in the battery box, and the fuse at the front of the battery to have good access. (Watch the pic)

The fatter wire from the battery goes to the front of the bike and under the fuel tank, where the coils live. I've done all connexions with travelling in mind: like every year I ride a lot of kilometres for Europe, in case of a relay breakdown I simply disconnect the relay wires on the OE connexions and re-connect the OE clamps.

The connexions are as follow (my bike is an European 3CV)

To earth: from relay n 85 connection to a chassis point

To battery: from relay n 30 connection to the positive

Red fatter wire from relay n 87 connection to the coils

Coils connexions


White female clamp: - Red/white wire: insulated                                                       White male clamp: - Red/white wire: red fatter wire from the relay from battery 87

          - Grey wire: connected by a grey wire with the white male clamp grey wire            - Grey wire: connected by a grey wire with the white female clamp grey wire


Yellow female clamp:  - Red/white wire: to the relay, to activate 86               Yellow male clamp:- Red/white wire: red fatter wire from the relay from battery orange wire

             - Orange: connected by a green wire with the yellow male clamp orange wire        - Orange: connected by a green wire with the yellow female clamp


Today Ive tested the new relay mod and, like Pat told me, new float bowls fuel level, 23 mm, from the previous 21mm.

Ive chosen the worst possible scenery: hot day temperature, curvy, tight, slow known road that go from level sea altitude to 2.000 m. high in 40 kms where I drive very hard form 2 - 6.000 rpm all the time in 2nd/3rd gear (more is impossible: you go to the ditch... and the ditch is at the bottom of a 500 m cliff. Scary! )

The bike accelerate with fierce power, Ive near eliminated the backfires... but Ive got HOT. Even with cold sparks and with big oil cooler, the oil went to 120C in 30 kms, when last week, with similar temperature, didn't pass from 105C in the 40 kms

So I revised the float bowls level one more time, leaving them in 22 mm
. little backfires have appeared again, but less than the OE settings, and the temperature have come back to proper leveles, between 80-100 C

IMPORTANT: the correct relay needed is at the right on the pic. The difference beteren the two relays is that the left one had a "make" and a "break" contact output. The right one has a double "make" output. 30 is connected to + battery. If there is a closed circuit over connections 85 and 86 the 30 is connected to 87, do thats the output. The other relais has also a 87a connection, which is connected to 30 if there is NO closed circuit beteren 85 and 87. It is a switchover relay. Ive learnt it by the hard way mode: I dismounted completely the carbs before to advertize it, because my revamped 1TX stalled at idle (well, it was in 2 cylinders only)



Colder plugs NGK DPR 9 EA 9


It is a good idea to change the 25 years old spark plug caps for a new ones. NGK VD05F caps fit in our FJ. Unscrew the OE caps, cut 1cm. of the wires to eliminate the oxidation and screw the new ones.

I obtained the idea from my Honda CBX 750 owners manual: living in Tenerife and riding long journeys in Mainland Spain too in spring or summer It's recommended the fitment of colder Spark plugs, NGK DPR EA9 or Splitfire SF416B. I've checked that the bike runs around 5 colder and feels sweeter too. Only for warm / template climates. When cold the engine doesn't get enough temperature and drinks oil



CLUTCH     See Changing the clutch fluid & hose

 Think that better clutch engagement means better shift gear movement, a good idea thinking about the agricultural feeling of the FJ gear change.

Additionally, The clutch lever itself is prone to wear on high mileages bikes and, as there not adjustment at the lever itself, it can have trouble engaging the master cylinder rod. The symptoms are the same that the other clutch faults: clunky gear changes and difficulty selecting neutral because the clutch is not able to fully disengage with its travel limited. When rebuilding your clutch, don't miss to change the lever!


Improving your clutch

- When slippage starts on your clutch, it is due to the weak OE clutch spring. When the spring worn, the plates start to warp & slip, and it is time to replace them. It is a good idea apply any of the following clutch springs ideas.

- When a new clutch kit is fitted, throw to the bin the wire clip (8) and the spring damping parts(4,5). See the parts at the picture.

The OE kit are 2 thin plates and 6 big ones. The thin plates are fitted one at the front (11) and one at the end of the plates (6). When the above pieces are removed, you can replace the last thin plate (11) with a big one. You will have 7 big plates and 1 thin, with improved clutch surface. The clutch feels more responsive and don't slip anymore at high rpms..

- I fitted a set of Barnett clutch plates in my 1100 when the originals ones started to slip. Ticker than the original ones, and no feeling differences at all. Now, I have fitted an EBC kit, reference number 2285, and even although is ticker than the OE ones too, there is no difference at all too

- Fit a metallic hose (Goodridge or similar). You get more pressure at the circuit.

- The cheap solution: fit another diaphragm spring on top of the OE, the only down side (and it is a BIG down side) is this leaves the clutch lever action a little heavy. This is the solution that I have just applied, and the lever is not too heavy, getting a very good clutch engagement and making the gear engagement more positive and less agricultural. But I've got a left hand injury too, so I've extirpated the 2nd spring.

- Install a Burnett clutch spring kit conversion.

At the photo you can see the FJ clutch spring compared with the XJR 1300s one. There is no difference at all!. It is exactly the same unit, with the same thickness. A total waste of money of you think that the XJR spring is harder

The cheapest and best solution is simply install the FJR 1300 clutch pressure spring. No extra hand power needed!. It is checked that the diaphragm spring from the FJR1300 is a beefed up version of our own FJ1200's. I have no tested this solution myself.


Clutch master cylinder conversion

It is recommended to change the clutch master cylinder to gain sweetness at the lever in conjunction with the improved clutch. The FJR master is the most popular conversion, because it fits straigh on, but because those are expensive 2nd hand, I opted to fit a ZZR 1100 master cylinder. It fits straight on too, only you must cut the little protruding piece of metal at the left side of the mounting bracket, to cleared space for the fitting. A tiny paint with a pencil and it looks like it is designed to fit onto the FJ.

You must adapt the connectors that fit on the clutch switch, but it is an easy task. With the change the clutch action is sweet, more positive engaged and you can regulate the lever to your size. RECOMMENDED


Gear shift

Horrible CRAAAK and CRONCH noises are continuously surging from the gear shift, concluding in a long term 2nd gear breakdown in FJ 1100 and FJ 1200 models. (And in FZ 750 first series too). The cure is to replace the gears with new parts and to replace the selector fork at the same time, an expensive fix, because it involves dismantling the crankcases. To prevent this, dont abuse of the 1st to 2nd high rpm changes and use good oil.

Factory shift kit: very cheap improvement: replace the shift spring with a harder one. The problem is getting there to change it: you have to disassembly clutch plates, clutch basket, gear lever, gear selector inside the right hand of the motor near 4 hours job and needing an expensive Yamaha special tool to dismount the clutch basket. The gear selector get so much harder than before, but the FJ1100 missing gears when changing at high revs don't happen anymore.


May 2.012: FACTORY SHIFT KIT (2)

The revised kit contains the same spring than before, the clutch gasket and a new shift inner lever with a little bearing instead the OE pressed-shim lever. The idea is that the new lever softened the harder spring.

It is NEEDED to buy the gear selector shaft oil ring, PN 93102-12321, because if there is an oil split after the assembly it is a hard work to change it again.

And it is RECOMMENDED to but the following parts:

PN 99006-10600-00 Gear selector shaft clip

PN 93109-12075 sprocket cover oil rings (2 units)

PN 5VK-18127-00 shift gear shaft spring stopper

PN 90215-25218 basket clutch nut blocker shim

It is a false economy no to change this parts: all of them are less than $12 and you're exposed to a oil split or a mechanical failure.

Like in the FJ 1100, it is necessary to dismount the front sprocket cover, gear selector shaft and clutch assembly including clutch box. So a clutch holder tool is necessary to dismount the big clutch basket nut (30" socket).

Take pictures at the gear selector drum and at the OE lever position. If the gear is in neutral, the lever is located in the only leg of the star-form gear drum that looks to be broken. Situate a rag to avoid the screw or the spring going into de sump and extract both and the lever at the same time. To fit the new lever and spring it is better get assisted by a friend: while you're installing the screw that holds the lever and spring in place, your friend must press the spring with a large flat screwdriver in order to take everything to place.

To reinstall the shift gear shaft, fit the shift gear shaft spring stopper screw with Nural 50 and fit electrical tape to the axle gear head to avoid to damage the new gear shaft oil ring.

The conclusion is clear: the 2 hours to fit the kit as described by the instructions are hyper optimistic: both my friend Mingo and myself are expert FJ owners and we dismantle our FJs with our eyes closed. And we last 3 and half hours. Apart for the company and the laughs, its is better to get help to dismount/refit the clutch basket screw (7 kgm.) and to install the new spring/lever and the screw.

Riding the bike: is it worth the expense and effort?. Mmmmmm... Yes and no. Let me explain:

You don't get a Suzuki type gearbox with the kit fitted, or even comparable to my Honda. The gear change continue being very noisy, and aggravated by a even harder shift than before, problem that is not completely fixed by the kit bearing type lever. If you do find traffic jams in your usual riding , or if you riding is calm type, going touring or using the gear change like a mere process to go form 1st to 5th, leaving the monster torque engine to do the job don't fit the kit.

On the other side, it is not expensive if you fit the kit yourself, even if it is not an easy work. And the gear engagement is much better, with less play at the shift lever making the changes much faster and precise, perfect to play with the guys with much modern tackle.

And if you own a FJ 1100 or 1986-87 FJ 1200 is a big improvement to avoid the 2nd gear problem that could affect to your bike

UPDATE JULY 2.012: after 10.000 kms the hard spring has just bed in and it is no more hard at all. The gear engage with less noise, less gearshift lever travel and more positive, resulting in a more pleasant riding, with less vibration, less effort on the up shifting and less worried about down shifting at high rpms.


August 2.013: RPM SHIFT KIT   

On March 2.013 we fitted a different shift kit on Mingos FJ: it is an evolution from the Factory kit made by RPM in CA, EEUU. The owner is an excellent chap that develop, built and sell spares and improvements specifically for our loved FJs, from shocks to special valve guide oil seals.

The kit improve the bearing and the lever and uses the OE spring, so the gear is not only much more precise from the 1st moment, its silky smooth since the first moment too. Randy, the owner, has got a BIG improvement over the Factory kit. IT IS FANTASTIC!. RECOMMENDED


October 2.017: gear lever trick


On June 2.017 when I bought my 1TX first thing that impressed me was the extreme precision on the gear change and the sweet and short gear lever movement. It is due to the situation of the gear lever that connect with the engine, like it is visible at the pic.

It is a very easy trick: simply dismount the lever to the engine, turn around 30 the lever and reconnect it, adapting the rod simply screwing it in both sides. Easy, and with excellent results at the gear lever movement and gear insertion, up gears or downshifting. RECOMMENDED




OIL LEVEL: IMPORTANT TIP the method describe to check the oil at the workshop and at the owners manuals is wrong!. These explain that the bike must be at work temperature, checking the level after 2 min with the engine switch off. My bike wasted around 0,5 litres per 1000 kms because I followed that procedure. Instead of, my friend Jose Carlos, long distance motorbike courier, told me to test to do it with a cold engine, let it overnight. In our past summer travel I started to check the oil level like J Carlos told me and the oil consumption was niggle!!!! even although 600 kms fast journeys. I checked then the KN filter and it was black, soaked in oil. It was clear that if you check the oil with the motor hot the engine throw away the oil by the breather hose to the air filter box

 There are millions of words written about oils and I have read a great part of them. My personal conclusions, based in my personal reading and experiences, are as follow:

Synthetic vs. mineral based oils: synthetic based oils are thinner and their molecules are more resistant to the enormous pressure forces generated between parts contacts inside the motor, and they are less affected for the temperatures. But be careful when you use it: you would never use synthetic in your motor before around 12.000 km from new because you will never get a good break-in: so much the oil lubricate parts than they dont get fitted together . Use mineral oil minimum the first 12.000 km

Brand oils and car vs. motorbike oils: I have read comparatives between different brand oils and car vs. motorbike oils. My conclusion: the moto brand only add price to your oil. And I worked in Audit Accounts multinational and I have see how in a refinery plant they make oil that after they carry it to a bottling-plant where the only thing that do is filing with the same oil different bottles with different brands.

So, when buy oil, look only at the SAE (or temperature) grade and API standard.

In reference to SAE, its recommended use 50w oil if you live in a hot climate (like me) or 5w in winter, in a cold place. It could be a good plan using mineral 20-50w oil in summer and 10-40w in winter.

The last API SJ motorcycle oils have a lot less of zddp (whatever they are) and a lot of saving fuel and anti- slippage additives. It seems that zddps are valve lubricants.

Specially in tuned motorbike motors the clutch slip with the new SJ rated oils, except are branded with the JS2 Japanese rating to motorcylce oils to avoid clutch slippage

Well, it seems that you must look for not a fuel saving rated oil. And, if it is possible, a SG rated oil, with more zddps and less anti-slippage additives. Krafft and Elf make SG oils.

And in the FJ, mineral oils are the oil to use, FJ air cooled motors, with big tolerances, drink synthetic oil. And with the temperature and the synthetic additives the valve guides oil rings get hardened and the FJ engine starts to spend oil without solution.

Today I use 20-50 w mineral oil, SG rated, and I change it with the filter every 6.000 kms. Sonic makes a good oil too, specially formulated for old-oil consumer motors


Bigger oil cooler 

I ordered from the FJOCUK. It seemed me a good idea to fit it to run cooler my loved FJ, because my last FJ 1200 were running too hot here in Tenerife because of the ignition advancer. And, like you know, in Tenerife the minimum average temperature are 18C.

 The instructions speech easy fitting was a mere marketing fantasy: get ready to swear and fight with the cooler for about 3 hours, and with a pair of spare hands to help you, because its near perfect finish and tight fit do it a pain in the **** to mount it. The most difficult part is to fit the old rigid hose to the new flexible hose: you must use a handsaw to separate the rigid part and you must be very carefully cutting it, because you could damage the rigid hose (like I did BOH!). And like the new cooler is rigid mounted, be ready to built your own flexible support with a pair of grommets.

As you can see, I bought a flexible car radiator grill and I cut a piece to protect the cooler from debris and stones, fixing it with the same cooler screws. The problem is that my bike runs between 5 - 10C hotter, so I can't recommended because you have spent a lot of money and swear to fix the cooler to return to the same place fitting the grill

The bike now looks gorgeous, and the finish of the cooler is excellent. I vigorously recommend it, even although only for the look of the thing.

And it is effective too: Mingo & myself bought a couple of oil thermometer at eBay. My bike runs between 80 to 100C and the Mingo's runs between 90 to 110C, so my bike runs consistently around a 10C cooler


     RPM Spin on oil filter conversion


When received I was amazed: it is an outstanding piece of kit!. It is a pity that you have to screw the oil filter into and no leave the aluminium piece at show.

The fitment is very easy even when Randy, the RPM owner, miss to send you the instructions. A bit of internet search and I assured that the long screw go into the engine (like looked logical at first impression). Soak the gasket on oil and with a 25 mm. head fit in 2 min... if you have the head, of course. I discovered that for 30 years I've never used that measure. Half an hour to make a fast visit to my local hardware store and ready. Be careful don't overtighten: it is not necessary. You can feel the end of the engine thread when screwing the nut.

Oil filter fitment is another 2 min. issue.

You don't trap the wire that is guided by the rear of the filter case, you don't loose that big shim that fit on the old filter, (so consequently you don't soak your hands in oil looking for it),  you don't have to refit a new inner & outer gaskets... Change the oil filter  is a doddle now.

To me the main advantage is about changing the oil filter during my travels: I don't carry a torque-wrench with me to give the 1.5 kgm. specified torque. And it is difficult with a head and a socket due to the spring pressure to get the correct torque, with the always pending danger of overtighten and destroy the engine thread and stay f**ked in the middle of nowhere, at 4.000 kms. from home and with an Ocean in the middle...

Another plus is that the engine carry a little more oil with the conversion, always a welcome gain.

And yesterday, on August 2.013, my bike run a little cooler than usually in a very hot day. (about 2 C) Its possible that the exposed total area to the air flow be wider now than with the OE case. I will confirm with my friends bikes.

I had only three concerns before to know and fit the kit:

1.- The filters specified on Randy site are difficult or impossible to find in Spain. Problem solved, because I checked that HI-FLOW 202 fit perfectly, and by coincidence it is the same that fit my CBX 750. Even in an emergency, any std Honda filter fit (even these are smaller)

2.- The main concern was the aesthetical issue. And it was not only me: all my friends were saying "f****ing horrible" and other less polite things. Well, NO, no way. The Randy pics don't do justice. (Sorry, Randy). The engine looks tricky now with the new filter and the spin on, even better than with the old ugly oil filter case protruding nut. Only take a look to my bike.

3.- We all know that the only weak point in our beloved FJs is the clutch push-road seal. Is it more exposed to the elements with the conversion?. There is no more means of debris to be able to reach the seal and 99% of the debris that does reach the seal is from the chain, so there is no concern from the spin on conversion. If anything is actually just the opposite happens now and it might keep the area cleaner. The stock canister housing has a lip that material could build up on and not drain/fall from the area. The round oil filter allows all moisture and debris to fall completely away from the bike and not get trapped by the lip on the housing. Anyway I will update this issue in a year of use and abuse...

IN CONCLUSION, my only complain now is not have tested this conversion before. IT IS FANTASTIC!. HIGHLY RECOMMENDED!


Left cranckcase oil seal change


Just seeing the oil leak, although very small, I though the worst: the original seal is made with a rim which is imbued in a groove inside the crankcase (the seal on the left in the photo) so all the signs were that it was going to be necessary to open the crankcase to change the seal.
But the ignition is a point where FJs do not carry oil pressure, so the replacement original Yamaha oil seal does not made with that edge, and change the seal is a simple task of removing the old seal with a screwdriver and fit the new one. The replacement measures are 34 48 7 when the original is 6, so the replacement is deeper than the OE one.
Anyway if you have this problem over the course of a holiday, in a travel, and you do not want to spot your boots with oil, it's okay to cover the tiny hole evacuation of water from the ignition cover with silicone and wait to arrive home to repair it. The ignition will work without problems.