Tips & Fixes


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FJs are sturdy mounts, and put up with hard riding for many years without complaint. They sometimes do have their quirks tough, and this section is devoted to the common fixes for little annoyances that add so much character to the bike.

See too Buying 2nd-hand FJ and SUSPENSION TUNNING and Clutch hose change


I think is due to FJ 1200 is a simple over bored FJ 1100, because I dont remember all those seismic vibrations in my 1100, that causes broken fairing tabs and screw drops in 1200 models until the 1991 on model, with special rubber in the chassis fittings.

Anyway, to minimize vibrations, here it is a little checking list:

1.- Check and repair the carb diaphragms. Below there is a method to repair these and avoid bankruptcy, because the Yamaha spares are very expensive.

2.- Its essential keeping the OE weighty bar ends.

3.- Dismount and grease the engine rubber mounts. Use red rubber grease. When refitting, apply the correct torque specified at the workshop manual, no more.

4.- Check the rim bearings.

5.- Fit the OE front sprocket. Its not so expensive and come with a vibration damper grommet inbuilt.

6.- Check the wheel alignment. The swing arm marks are useful. Do it taking measures from both sides of the swing arm.

7.- Of course, all of above is starting from a correct carb balance and valve clearances checked.



It seems that the regulator hot left engine position causes that it start overcharging and it causes the battery fluid boils and evaporate, leaving the battery dead. It is commented that Yamaha fitted the sealed battery to 91 on models to avoid this splashed fluid problem, because sealed batteries dont contain fluid, and, obviously, it can't boil.

OE regulator is overly overpriced so try one from ELECTREX part n RG25. Cheap and dead easy to fit with the instructions supplied. 7 years since fitted, the regulator works perfectly. and the service support is top notch: near 3 years after I bought the regulator, they answered my mail with a technical question NEXT DAY! TOP NOTCH! (Read it at the FJ medical centre section)

Update: Electrex don't make this regulator anymore. Buy the Nippon Denson, not a cheap Chinese one


 Fuel starvation 

In older models, it seems to be a problem with the venting of the gas cap not letting enough air in, and this builds up a vacuum in the tank, starving the carbs. The permanent fix for this involved disassembling the gas cap and removing these 2 little orange pieces of rubber that are supposed to act as some kind of vapour valve. See the fuel tank cap trick in the carburetion section 


Bouncing speedometer 

Unfortunately there doesnt seem to be one solution to this problem. I have read about to disassembly the clocks and sprayed with silicone-based oil. Myself I sprayed with WD40 and it works. Not easy solution anyway. And I DON'T RECOMMEND painting the speedo & tacho needles with nail paint. You can't see anything at night. Tested. :-(


Sump plug screw and threads stripped 

It is definitely an ugly problem of the FJ models: when tightening the sum plug I have stripped 2 times the threads along the time. My 1st time was in 1992 in my FJ 1100 and now it is my 2nd time in my FJ 1200. And it is not due to over tightening.

Like a prevention, use always a new gasket.

Fixing is not difficult, only time consumer: you have to dismount exhausts and oil pan. Fortunately, It is not necessary to take the motor off the chassis, only the oil pan. Fit an helicoid and refit all again


Rear shock mudguard 

I bought a car mud flap with the Yamaha logo printed, drilled the bike guard with a 8 mm drill and attached with a couple of screws


Clutch bleeding    see too      Clutch hose change

After a lot of hours bleeding my FJs clutches when I changed the hose, a car mechanic told me the best solution, the same that in Peugeot 504 models: simply, refill the circuit, close the nipple of the push-rod, left the master cylinder deposit open and push the lever one hundred times (or similar, UFF!). You will see the air pumps going out the circuit. After a quarter of an hour, more or less, you will get your circuit free of air.


Exhaust refitting

When refitting exhausts, if you re-use the gaskets , apply a special-exhaust paste that you can buy in any auto-store. Fit the exhaust, ride around the bike to let the exhaust get hot and retighten the screws with the exhaust at working temperature. And be careful do not to touch any part of the exhausts directly with your skin!!!!.


Head bearings 

Replace of the head bearings is my worst nightmare in the FJs. I changed them 10 years ago in my FJ 1100 and again in my new FJ last June. It is near impossible to follow the workshop manual procedure: punch the inner bearing races with a screwdriver and a hammer: there is no area to base the screwdriver to push the down bearing race.

In my 1100, I got take out the down head race welding a piece of iron to have area to punch it out, and in my 1200 with a little radial-saw, mm to mm grinding for 10 hours the race surface until it collapse, being horrified for the possibility of damage the chassis inner head

There is other method in my mechanical consultory section.

IMPORTANT NOTE: the grommet with the n 5 at the part catalogue in the picture at the left is necessary in order to get the proper bearing torque. If discarded, when the torque is applied at the head nut (n 7) the bearings get too much tightened.

FJ 1100 front collector's double wall

FJ 1100s fit a double wall headers that suffer from inner cracks and those sound like piston/conrods failure. You can live with the noise and it doesn't affect the motor health. This problem was solvent by Yamaha fitting a single wall headers in the FJ 1200 models, and by me in my first FJ 1100 buying a Muzzy exhaust.


Don't fit economy transmission kits. Any chain with less quality than top of the range (and expensive) DID ZXVM chain is money throw to the bin. I clean the chain each 1.000 km. with WD40, grease it (with a Teflon free product to avoid road grim pasted and actuating like grind paste) and clean the excess with linen. I obtain around 100.000 kms. from my chains.

Fork oil

You can change the fork oil without dismantle the fork legs from the bike, thanks to the plug screw at the bottom of each fork vase. But if you use this way, you will only get about 300 cc of fork oil, instead of the 395 cc to 425 cc that there is inside of each leg. Particularly, I prefer dismantle the legs to be sure I have plugged all the old oil, and adjust levels and quantities with completely new oil.

Carb Diaphragm repair

My carbs had 2 carb slides diaphragms with various little holes. The consequences are poor fuel consumption and vibration. The OE spares are very expensive (about 200 ), even although at the FJOCUK are cheaper because they are exchange basis: you send your slides and they fit the diaphragms.

Anyway, you can use Plasti-Dip. The 1st problem was found it: in Tenerife nobody know what I was speaking about, and I visited A LOT of hardware and auto store shops. So I had to order to Britain: the post was more expensive than the Plasti-Dip, so I ordered a pair of bottles. Total cost: 40 from . Buy it at FROST

Well, It is FANTASTIC!. I mixed it with 20% naphtha and painted the diaphragm holes with a pencil, allowing to dry overnight. Ready!. It is near the OE flexibility and they look more resistant than before. Job done. I've checked a couple of times in 12 years and the fixing are permanent


Carb manifolds fitting

The carb to airbox manifolds get hardened with the engine hot & by years, so it could be near impossible to fit them properly. It is even more difficult in my CBX than in my FJ because there are not heat windshield protecting the carbs and consequently the parts are even more hard to bend and manipulate to refit them. The trick can be used with any other grommet part on the bike to soften it

The solution is easy: buy new parts, but expensive. So boil the parts 5 min in water 5 min and then immerse the parts in liquid Vaseline for 12 hours. The parts recover most of their flexibility and you need less effort to refit these. IMPORTANT NOTE: it is recommended only for single or leaving alone people. Don't do it with your couple/mother/wife at home because the refitting process could be peanuts compared with the consequences of using her cook ;-)

Valve clearances & Ford valve shims

Valve clearances on race bikes are settled on minimum clearance the intake valves and maximun on exhaust valves, between specs, so the combustion chamber get a optimum emptied in each complete piston stroke. In our FJ the adjustment used on race bikes are 0.11-0.12 intake and 0.20-0.21 exhaust.

Getting these precise adjustment in our FJs is very complicated because the Yamaha shims are made with a 0.05 gap between sizes. Well, the solution reside on fitting 25 mm. Ford valve shims, with a gap of only 0.025 between sizes. On the pic there is a table with valve sizes and Ford part numbers. As far as I know, the parts numbers are for European Ford models, ZETEC 1.4 engines.

At the left are the shim sizes with UK & Spain part numbers.


Headlamp adjuster repaired

Dead easy and cheap, the trick come from a Spanish FJowner, member of our FJ whatsupp Spanish community

Buy an RC radio control car trasmission cardan from Aliexpress. The perfect sizes are 5x6, but 6x6 do the task too. Fit it to the remote dipstick and to the headlamp. Ready. With the allen screws provided to fix the cardan you could dismount it if you like.

Clever and simply!