Mech

Anyway Valkman, unless the oil you have is totally unsuitable for a wet clutch, which seems unlikely given you use it in your bikes, I think you are going to have to take the side cover off and inspect and measure both clutches. I'd recheck the clutch adjustment first though and perhaps try adjusting it with a bit more play than suggested just to make sure there isn't a bit too much stiffness in the cable or gear change linkages or anything.

Gee you guys. We've had wet clutches for more than a hundred years, and the manufacturers know quite a bit about their design and operation... What do you think we were doing for oils before the jaso standards were set ? We were doing what suzuki and every other bike manufacturer was telling us.. Using a suitable oil. They recommend a suitable oil, but it was never any jaso standard. Now that we have modern cars and modern oils to choose from and a lot more additives than we used to, then sure we need to be careful what we do put in our bikes, but it doesn't mean that only the jaso certified oils are safe. Just because some of you put some sort of car or truck engine oil in your bike and then had a slipping clutch, it doesn't mean we are all going to put the wrong oil in... If we follow the manufacturers recommendations and read the oil's label we will be right.. Old suzuki's do not have to have jaso certified oils in them.. There was no jaso oil spec when they came out... They ran fine for years with common old mineral oils. Please stop insisting that we have to use jaso certified oils.. It's not true. There are heaps of oils out there that are of better quality and imminently suitable, and cheaper, than some of the bike shop oils that have a jaso rating.

So that splined bit is part of the carb ? Very strange and surely not for a hose to go on..

There's different grades and brands of 4T.. The book says... "Use only a high quality detergent IOW/40 motor oi l with an API classification of SF or SG.".

I'd doubt the oil is the problem. The clutches aren't too fussy about the oil as long as it's an engine oil of the correct viscosity. Unfortunately it's really hard to differentiate between the centrifugal clutch and the multiplate clutch when you are trying to diagnose them. You can use the shift lever to slip the plate clutch momentarily as you are accelerating at a rev above centrifugal clutch lockup speed and sometimes they will start slipping bad then, which suggests it is the plate clutch, but it's far from conclusive. If the problem only happens at take off, and then seems fine once the revs are up, it tends to suggest it's the centrifugal, but again it's not conclusive. Luckily the two clutches are both together in the one side case, which can be got off in place, and are components we can inspect and measure once they are apart. That is really the only way to be sure you are fixing the right clutch.

I'd try blowing down it and see where it goes. It might be blocked off. On a Suzuki there is normally a float chamber vent just around the corner from there on a flat you can see shaped like a figure eight. The vent is drilled into the top of that figure eight.. If there's no other vent then that's probably what it's for. Blowing will tell you..

Ha, that's crazy cheap. At that price you could keep one in your tool kit..

The book I looked in says the 4wd has a screw, but the 2wd doesn't show anything.. Presumably a plastic lug or clip ?

My internet's too sh** to see the video today Parham, but good work getting it going.. I'll try looking later. I don't know what technique you use with the pull start, but the suzuki owners manual suggests an unusual way of using the decompression lever when using it. Most things you just lift the decomp and then pull the starter. Suzuki say to lift the decomp and then pull the starter very slowly till the decomp lever just flips itself back to the closed valve position, then let the rope right back in, gently engage the pull start and then give it a hard pull. It's a good system. It means you've parked the engine with the exhaust valve just closed and all ready to start an intake stroke, and still leave the motor enough turns to get up to speed before the next compression.. You get full charge of air and fuel, easy pull and a reliable start.. Ha.. and now my internet goes and I see you follow suzuki's way already.. I only read about it a while back after years of struggling to get bikes to pull start..

"Wide open throttle". Gwb... This is a good forum Rgeiser.. friendly, helpful, and not full of pedants arguing about hypothetical ideals..

Don't know that one Mga.. Some have several wires.. But if you are sure those are the only wires then presumably a switch would do it.

I'd doubt the hose goes to the instrument panel.. They have an engine and airbox venting hose that runs up under the range/rev/4wd panel where it branches and runs back down as two open breather hoses.. You might be blowing into one of them. I'd try and aim it downwards so it doesn't accumulate water or dirt. I'd also change that fuel hose going onto the carb.. It looks like it's old or the wrong size and wall thickness.

They can get vacuum leaks where the carby fit on.. And you should check the egr valve is closing..

Has it got good compression ? Have you checked for vacuum leaks ?

Yup check the pressure with a gauge..

I think the parts places are pretty dependable, if they say your part will fit another model then it will, and the other model part will fit yours. It's easy to cross check. Look up your part and see what else it fits, then look up some of those models and see if their part is said to fit your bike, then if you really want to check their info, go to another parts site and repeat the whole process. You may find that your part is available under another part number. Sometimes under several numbers. Also, I'd consider pulling that bent arm and straightening it. The suspension and the wheel alignments on these things really aren't too critical They can be a bit misaligned and still track fine and have no problems.

I don't know what those symbols on the carb mean.. Off will be horizontal though.. I don't recognise that carb from the hose layout, it's not the standard carb we get here, but I think that hose at the top center in the last photo would be a vacuum, either for the pump or the tap, and there is probably another vacuum port for the other, possibly that plugged one. It's usual to have a bigger hose going to the pump, and a smaller hose going to the tap. The two vacuum ports have fittings to suit. In the first photo there's a hose opening upwards, that doesn't look right.. if it's a breather it should be aiming down to keep crap out. And the fuel hose in that photo looks about ready to split where it goes on the carby.. If that was a standard suzuki carb that up facing hose would be a vacuum hose I think. On the carbs around here, the left side of the carb has from front to back, a small vacuum hose fitting(pressed steel pipe) aiming up, then a larger vacuum hose fitting(machined brass) also aiming up, then the fuel at the rear(machined brass) also aiming up, and on the right rear there is a breather hose fitting facing down. I'll have a look later and see if I have an old carb like that to check what the ports are..

Nice Ulf. Nice clear picture, and the view from the top would be worth a walk let alone a ride..

You need to have a look at your fuel tap and see if it has a vacuum hose on the back of it. If it has a vacuum hose then that tap has no off position. In normal use you leave it on run or reserve and when the motor stops the lack of vacuum closes off the tap, when it fires up the vacuum opens the tap. The middle position of the tap is called prime and it's on all the time, it's for filling the carb if it's empty and there is no vacuum. If you don't know it's a vacuum operated tap and turn it to the middle position when you get off you are bound to get a flooded motor. If the tap is playing up it can fail to close when the motor's stopped. It only needs a speck of rust under the vacuum operated needle and seat in the tap to make it stay open, then you've got three on positions and no off. They can also get a hole in the diaphragm that operates the tap. If the diaphragm has a hole fuel goes down the vacuum hose into the motor. Lots of float needles leak a tiny amount, not enough to effect the running but enough to fill the sump with fuel when they sit for a while. The tap is the first and most important thing to get right. The manual taps can also develop leaks. There's a rubber washer in the manual tap with holes in it. On some models it's possible to flip the washer over so you are using the new unworn side. I'd make sure the tap was turning off completely before buying a new float needle.. It's easier just to pull the hose off and check there are no drips..

Also Mga, it's always worth looikng up the parts online, then seeing what other models they fit, because often the other model uses a different part number, and sometimes that other part number is available. They change the numbers if it's a superseded part, or got a different colored paint or any number of trivial things..

I don't know whether it applies to yamahas but some makes and models have different suspension arms in different years, some are longer to make the bike wider. It's something to watch out for if buying second hand parts.

Undo the carb drain bung and make sure the fuel is getting right through the carb. Just because it's getting to the carb doesn't necessarily mean it's getting into the carb. Have you tried a new spark plug. It could be as simple as that. And what about this question ... "So bogs and then just stays the same, struggling to go faster ? Or does it start dying out.. Actually get slower." "

Inside the guts of it there's a centrifugal clutch which is used at takeoff, and another clutch, a multi plate clutch, that's operated off the gear shift mechanism. The multi plate's there so when you change gears at a rev above the centrifugal clutches lock up speed, the gears don't graunch or be hard to slip in and out. The shift mechanism slips the clutch before the gear's start to move in or out of gear. That clutch operating is probably that "mushy" feel you detected (just an incidental bit of info). You should check the adjustment of that multi plate clutch. It's on the right behind the rear wheel, behind a bung. If it's not slipping enough they are hard to shift. The real secret to good changes though is in A: getting the torque load off the gears at the instant you move the lever, and B: synchronizing the speeds of the gears. The process when changing up is , give it a little extra throttle(more than you had been) just before the lever gets moved, so the bike is accelerating, then throttle off just as you move the lever. That way the bike and the engine are both under a sort of float condition, both are neither accelerating or decelerating. The process when changing down is throttle off till the revs are low enough to change down, then blip the throttle just at the instant you are moving the lever down a gear. The throttling on takes the load off the gears you are in, and then brings the revs on the lower gear shaft up to the speed of the other shaft and gears. Depending how fast you are going at the time and the gears being shifted you sometimes need to give it quite a rev, but at low speeds just a little rev.

Onya.. Cheers.

Put it in two wheel drive, high ratio, and try rotating the rear wheels.. While you have it up.