FJ Owners Club

Q; When riding at about 40-50 mph and I take my hands off the bars the bike wobbles, how can I cure this?

Q; Just off tick over there is a chain rattle from the engine,

Q; My oil level light comes on, especially when going up hill.

Q; The brake lever takes two pulls before it bites correctly, does it need bleeding?

Q; My FJ is burning a lot of oil and need topping up but I cant seem to see any excessive smoke.

Q; Have a noise from the front end when going over bumps at slow speed, I’m sure its my head bearing that are knocking even though they seem correctly adjusted.

.Q; My FJ vibrates at 4,000 rev

Q; What bolts do I need to remove to gain access to the gearbox sprocket.

Q; The front tyre has worn on the right hand side.

Q;Are Radial tyres ok for the FJ

What grade of fuel is recommended for the FJ.

Frequently Asked Questions

fj1200-black
fj1100-black

Answer; Don’t take your hands off the handle bars!
It’s a common question and I’m always amazed why anyone would take there hands off the bars but I understand your concern. As to why a bike feels unstable at those speeds. It’s down to some extent to dynamics, best explained when you take a look at a shopping trolley, the front wheels seems to have a mind of there own at a slow speed until enough momentum is achieved. Basically due to the castor of the head stock and the trial of the forks this can produce a slight instability.
Their is checks you can do to insure your bike is at its best, because any faults will only exaggerate the problem.
1) Tyres and pressures.
Set to high speeds settings which is 36psi front, 41 psi rear. Check tread depth, minimum is 1mm but even if its close to this limit it will cause a problem and make the bike feel unstable.
2) Wheel bearings.
Grab top and bottom rear wheel and rock feeling for any slight knocking or movement. Front is best done by holding the wheel with your two legs and with your hands move handlebars sideways. Again feel through the legs for any movement or knocking. Any signs of wear best to replace.
3) Steering head bearing.
Before you can check for wear you must make sure they are adjusted correctly. The best procedure is to use a spring gauge (see Tech Info). Basically raise the front end, flip the bars, they should only move a few mm and stop, if they full onto the stops then they are too loose. Adjust until they support themselves. Now they are correctly adjusted, using your finger tips grab the bar end weight and feel for any roughness as you pass the centre point. Any tightening they are U/S and need
4) Wheel alignment;
First check that the chain adjusters are set to the same setting, these are the lines scribed onto the adjuster, this will insure that the wheel is parallel to the swingarm and in turn should be true to frame. Using two straight edges align against the tyre each side. Straighten front wheel so its parallel to the straight edge. If you have perfect alignment the gap on each side of the front wheel will be equal.
5: Suspension;
Check that you have movement and are not too stiff, they should return smoothly. Test by sitting on the bike and with gentle body movement the forks should the move and again same with rear. (see Tech Info for full details)
6; Top box or luggage;
If you ride solo with a topbox, then this will always upset low speed handling. The bike is always more stable when two up, even with a full luggage system filled up to bursting point. The reasoning is with more weight on the back this effects the steering geometer. Always worth riding the bike without the luggage and check the effects. If all this fails to cure the wobble. Keep both hands on the bars!

A; This is the starter chain, referred to in the OE parts listing as a Primary chain. The problem is due to the fact there is no tensioner so it rattles against the blade. If the noise happens whilst ticking over then checking and adjusting the valve clearance and balancing the carbs should stop this. If you want to replace chain be warned the motor has to be stripped down to the crank.

A; The level should be checked when the engine is WARM, not cold.
The general rule is; Dipsticks are checked cold, sight glass when warm. Best time to check level is after refuelling. The time taken to pay, will of given chance for the oil to return to the sump and most forecourts are level. Note from low to high is approximately 1 litre.

.A; The reason is due to brake pistons are too far away from the discs and on the first pull the piston simply push the pads closer to the discs and you need to grab again to apply pressure from pad to discs. The reason for this can be two faults.
1) The brake seals are grabbing the piston instead of allowing it to slide pass. The result is when you realise the lever the seals pull the pistons back off pads. The fix is to replace the seals.
2) Check the discs to see if warped, even being only slightly out can push the pads back in and so the piston are further into the calipers than normal, so the double pull is making them travel the extra distance back. The fix is the replace warped discs.

A; Only two ways that an engine can burn oil is either passing the valve seals or the piston rings.
First step is to check the compression. If cold then this should be around 120psi, hot 150psi. (also check they read the same within 10psi, any more than that and the engine needs stripping).
To check rings, add a few drops of oil into the weakest barrel, then turn the engine over (with plugs out) on starter, then recheck compression. If this has increase dramatically then the rings are U/S. If it make no difference then I should be looking to replace the valve seals and lap the valves in. The reason that it might be the seals is these tend to harden over time due to many heat cycles, this prevents a good seal forming around the valve.

A; Obviously make sure the head bearing is adjusted and measured the friction with a Spring Gauge, please details in the Tech Info pages.
The answer is quite simple but most members wont believe me. it’s the brake pads rattling. This is good new as it means the brake pistons/pads aren’t seized. I know your going to say ‘it’s a metallically noise’ but if you actually tap them they will make this noise. For all those who are ‘Doubting Thomas’s’ when you hear this noise, lightly grab the brakes, it should disappear

A; The Early FJ’s 84 to 90 have a solid mounted engine and its normal to have a slight vibration patch between 3,500 and 4,000 revs. If it seems a bit excessive then you need to check the carb diaphragms on each carb. Its easy to check, though if you have difficulty undoing the carb top screws you can’t use an impact driver as
1) its rubber mounted on the inlets so will simply absorb the impact.
2) It could result in snapping the edges off.
The answer is to use a centre punch on the screw heads or remove carbs and fit in a vice to get a better grip on head with driver.
Take a look at the diaphragms for holes or excessive wear. The reason why they make the bike vibrate is they don’t raise up together so giving each cylinder a different mixture and causing an inbalance. The fix is to replace the diaphragms.
Note; The later models (91-95) have a rubber mounted engine which should only have a slight vibration at 2,500 revs. This was designed into the bike. So if this vibrates further up the rev range this is not correct and you will need to check the carbs, see above.
Another check is a compression check, if you find a difference between each cylinder of more than 10psi this will also cause in balance.

A; There is a total of 6 bolts, three are obvious but the other three hold the clutch slave cylinder unit on.

A; The camber of the road increases the wear on the right hand side, perfectly normal.

A; No. Yamaha designed the rims to run on Crossply tyres. If you fit radials the front will be distorted in shape because its design for a 3.5” rim width. The rear will wear flat in the centre due to the radial tyre flexing, which is how radails are designed to work.
The Crossply have stiff walls as the rims are not wide enough to support the tyre.

A; Designed to run on basic unleaded petrol. All modern bikes have been since the 70's