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Fizz

what more to order?

30 posts in this topic

Hi everybody!

I´m about to make an order from TT´s OEM parts store to my 2002 Yamaha 426, i´m buying cam chain, tensioner and the dampers.

As i live in Sweden the shipping is pretty expensive, so i´d thought i´d order as much parts as i can afford.

The questions is this; what other parts should i buy? Parts that wear, and i´ll have to change at some point ...

Some parts that are cheaper to buy aftermarket over here, such as; suspension and linkage bearings, pistons etc. can be left out ..

So, parts that is good to buy OEM quality, and will fail soner or later ....

Thanks in advance! :thumbsup:

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Hi everybody!

I´m about to make an order from TT´s OEM parts store to my 2002 Yamaha 426, i´m buying cam chain, tensioner and the dampers.

As i live in Sweden the shipping is pretty expensive, so i´d thought i´d order as much parts as i can afford.

The questions is this; what other parts should i buy? Parts that wear, and i´ll have to change at some point ...

Some parts that are cheaper to buy aftermarket over here, such as; suspension and linkage bearings, pistons etc. can be left out ..

So, parts that is good to buy OEM quality, and will fail soner or later ....

Thanks in advance! :thumbsup:

I'd say nothing. Not even the camchain tensioners. The bike is strong, and what might break is anybody's guess. Oil, filters (air and oil), spark plugs is all any modern bike needs on a periodic basis. For the rest, just deal with it, when and IF it happens. My 2c.

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My 01 426 has been awesome but decided to do a new top end. When i got everything out and looked at the connecting rod and pin it had some ware. I would get a rod kit to add to your stash. :thumbsup:

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I'd say nothing. Not even the camchain tensioners. The bike is strong, and what might break is anybody's guess. Oil, filters (air and oil), spark plugs is all any modern bike needs on a periodic basis. For the rest, just deal with it, when and IF it happens. My 2c.

well, thats the problem ... nothing ever happens ... the machine never breaks down, so i´d thought i´d do some maintenance just to get to see the inside of the engine .. :thumbsup:

so you think i should save up for the "big bang" instead? :thumbsup:

My 01 426 has been awesome but decided to do a new top end. When i got everything out and looked at the connecting rod and pin it had some ware. I would get a rod kit to add to your stash. :bonk:

thanks for the tip!

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i would just save up for the "big bang". I just ahd it and damn was it expensive. people are right when they go .....they really go

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i would just save up for the "big bang". I just ahd it and damn was it expensive. people are right when they go .....they really go

what went down in your case, and what bill did you end up with? ..

a friend of mine had a valve that went into two pieces, and that ended up at app. $3300 to fix ... dont know exactly what parts broke, but i guess everything above the crankcase .... :thumbsup:

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what went down in your case, and what bill did you end up with? ..

a friend of mine had a valve that went into two pieces, and that ended up at app. $3300 to fix ... dont know exactly what parts broke, but i guess everything above the crankcase .... :thumbsup:

Wow! That's what I paid for my bike.

I'd have bought a good used bike, swapped the engine, switch the better "stuff" and sold all else on Ebay. Might have cost him less then 1/2 when it was all sold off.

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well, the bikes are a bit more expensive over here, for comparison, 2000 yzf426 goes for app. $3100 and a '01 for like $3400 .. a '02 for like $3600 ...

dont know which year his bike was though ..

the parts are more expensive also .. a cam chain that costs $35 at the TT OEM store costs app. $100 over here ...

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another question, how much do i have to dismantle before i can change the cam chain?

in the manual its only described in the crankcase section, and i dont want to go that far ..

is it enough to remove the cams, cover on the ignition side, and the ignition itself?

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another question, how much do i have to dismantle before i can change the cam chain?

in the manual its only described in the crankcase section, and i dont want to go that far ..

is it enough to remove the cams, cover on the ignition side, and the ignition itself?

I ended up taking off the head and barrel to do my cam chain,maybe someone who knows more will tell you different,i changed the piston rings while i was in there too.Parts are a rip off over here as well.The cam chain cost £48,but we have to pay import duty if we buy out of europe.

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Get a mag cover gasket, 90% of the time you can reuse it, but 10% of the time it will leak. I would also get the washer that goes between the front sprocket and the nut, it has a tab that folds over the nut to lock it in place. I changed my sprocket the other day and the tab broke off.

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Get a mag cover gasket, 90% of the time you can reuse it, but 10% of the time it will leak. I would also get the washer that goes between the front sprocket and the nut, it has a tab that folds over the nut to lock it in place. I changed my sprocket the other day and the tab broke off.

thanks! i accually had a few of those washers on the list! (they cost 5 bucks over here.. :thumbsup: )

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Switching out the cam chain for preventative purposes is both simple and very wise. Leaving them in too long wears the crank sprocket, which cannot be independently replaced.

Start and run the bike for just long enough to clear the sump of oil. Remove the cam cover and check the valve clearances in case any of them need correcting, as this will be the perfect time for that.. Remove the ignition cover (no significant oil will be lost), flywheel (puller required, don't cheat), and stator plate (#27 Torx bit required). Remove the tensioner (see manual for unloading instructions) and the two bolts holding the bottom of the rear chain guide shoe. Rotate the bottom end of this part outward and remove it by pulling it down. If it seems too stubborn to be removed, just leave it in the tower.

Remove at least one cam (probably both will be required) and rotate the chain off the crank as you did the rear guide.

In reassembling, you have a couple of options:

a) place to the chain over the crank and bolt the rear guide back in place. Reinstall the stator and flywheel, and depend on the front and rear guides to keep the chain from looping off the bottom of the crank sprocket as they are designed to while you time and assemble the top. Probably safe, but you always find yourself wondering if the chain is really on right.

:thumbsup: Remove the spark plug and use a screwdriver to find TDC, or eyeball it by lining up the flywheel key with the bore centerline and time and assemble the chain and cams with the whole run of chain visible. Foolproof, but be sure to double check the timing by pushing the flywheel and cover on by hand and using the real marks just before torquing everything all the way up. You don't want to have to take any more apart than necessary if you screw up.

I use option b myself.

Two mistakes commonly made are failing to torque the cam caps right, and timing the cams wrong because the cams weren't rolled back. Back the engine up to a few degrees before TDC, and then roll each cam back until the front run of chain is tight, and the slack is on the back side. Now, hold pressure against the rear guide shoe by pushing your finger through the tensioner hole and rotate the engine forward back to TDC. Then check the timing. Note that there's no point in worrying too much about the timing marks lining up perfectly. The marks simply are never going to be perfect. What you do is imagine the timing marks on in the same position on the next tooth, and see how that would look. If it makes it closer, move it. If not, it's OK.

Always carefully torque up the cam caps in three successively tighter steps. I use 75 in/lb instead of 86. 86 just seems too tight to me, and I believe Yamaha has reduced that value for the later models.

Sköl :thumbsup:

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grayracer <- thanks for the info! i´m not sure if i could afford a "big bang" ...

no more stuff to order at the same time?

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Hey Fizz how ya doing? Just chiming in hear, it sounds like what you are doing is correct with the timing chain and so forth. But there is something every one thinks they can neglect because it is made out of strong light Titanium, the valves. I come from a background of auto racing, SCCA Trans Am cars, you may or may not know of the series over here in the US and we use Ti exclusivley in the engines because you have to to stay competive. What you don't here very often is how often we change those valves, in our V8s the Ti exhaust valves are changed every 10 hours and the Ti intakes are changed evry 15 hours. Now in motorcycle you will gain much longevity due to the reduced weight and loading, but how long is the key to engine survival. If you can contact an honest engine builder they should be able to give a time estimate on when they should be replaced before they fail. Because when a valve drops it destroys component especially in light wieght motorcycle engines. Anyway Titanium is poor material for longevity overtime when exposed to tension forces and heat. It is a common misconception that Ti will last forever in an engine. My main expertise is american V8 engines, and I have stayed away from the Japanese Ti valved bikes do to the high maintence cost of the Ti valves, that is why I have a stainlees steel valved YZ400F. There are many more aspects to these engines that I am not going to go into in this post. If you want more info let me know. I do all my own work except for crankshaft rebuilding and specialized machining. My local motrcycle mechanic has rebuilt 30 Honda CRFs (yeah you guessed it Ti valve failures) an approximately 12 YZFs and YFZs (quads) 450s. If you want I can talk to him to get some sort of idea on the Ti valve life in the Yamahas. There is also an interesting mod you can do to the timing chain to make it last longer because stretched timing chains are an age old problem in these typs of machines I will explain more if you want just PM me if you want anymore info. Check your oil pump! I can't stress that enough as long as you have good oil and oil pressure the bearing should last very long but pistons pins always get abused. It just depends how far you want to tear into the motor.

Now I have to quit writing.

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bnio<- thanks for the input ... i wont dig to deep into it .... some info on how long the ti valves live would be nice though ...

everybody<- getting closer ...

anymore ideas?

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I absolutely disagree on the longevity of Ti valves. Mine are still in good condition in their 3rd season, and that seems to be typical. In fact, a lot of the '01 426's are just now beginning to wear them out. They can and do fail, but in almost every case, it is because the user ran them in a worn condition for too long, trying to squeeze the last bit out of them.

Yamaha uses very high grade aircraft quality titanium for their valves, and does an exceptional job of hard coating them, and of matching the seat materials to eliminate wear. They will literally go for years, not wearing enough to even require a clearance adjustment. But eventually, they do close up a little, and that's when you should start to watch them closely. When the wear is enough to require a shim size more than .15mm smaller than the original, it's time to replace them. Once they have reached this point, the hard coating is pretty much cut through, and they won't hold adjustment for more than 3-4 hours anyway.

But here's the real problem: As they wear, the wear may proceed unevenly from one side of the valve face to the other. What this does is to cause the head of the valve to scoot to one side as it seats, placing a bending load on the valve stem. If this load is high enough, and continues for a long enough time, the stem can break, dropping the valve head.

Except for this, and broken valve springs, the ti valves in YZF's very, very seldom ever fail. Replace them every ten hours if you want. But that's $450 for the valves alone, and most of them will go 10-20 times that long quite easily. Why Honda and the others can't do this mystifies me.

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grayracer <- thanks for the info .. but how (and when) do i check for wear? ... is it possible to change the Ti valves to stainless or anything else?

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