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i measured my chain slack today and the stock chain moves almost 60 mm. thats a little sloppy right? well, what should it be at? 40mm? should i just dump that stock chain anyways? i also am thinking of re-gearing in the future, maybe in a couple months, what sprockets should i get if i want more hi-end speed but still have the hp?

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you should ignore the manual for this too. The recommended slack is the same they recommend for sportbikes with 4" of travel. The easiest way I have found to check the chain was recommended here by bronco or noble, dont remember which: 3 fingers tall on their side at the point where the chain slider ends on the top of the swingarm-like measuring Scotch on a Saturday night. It works out to about 3" of slack-about 60mm. You can run looser or a bit tighter.

Don't use tacky chain lube, it holds grit/dust in suspension, effectively creating a fine cut-polish which wears chains out very fast. I use wd40 and have for 20+years with excellent results and no down side.

You cannot keep power (torque actually) and gear taller. You have to give up one to get the other, that is the nature of mechanical advantage-it is like using a longer fishing rod, the speed will go up but the force will go down. I wouldn't run taller than stock 15/44. I have a 41 t rear sprocket I bought when the bike was new and I thought I wanted more top end but I have never put it on. I cant justify it and it would ruin the bike off road.

Chain: I go to a catalogue somewhere (online or at a dealer) and pick through until I find what I'm looking for. I go for the highest tensile strength and hardness (Reynolds number) I can find. I am currently running a DID chain listed for a gsxr1000. I think it will be able to handle the monster 400S :thumbsup:

I run 14/44 and cruise highways at 130km/h (that's around 80mph) and can pick my way through the woods and climb hills just fine.

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Another way you can do it is to push the chain down at the end of the slider and it should just touch it :thumbsup:

Oh and I've been recommending either the above method and/or the three fingered one for quite a while now.

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Oh and I've been recommending either the above method and/or the three fingered one for quite a while now.

:thumbsup:

sorry, might have been you instead, been a year or so since that post. :ride:

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Is the WD-40 ok for the o-rings? Also wouldn't just evaporate leaving no lubrication? I have been using that tacky oil that they charge a fortune for and I agree it just attracts crud.

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Is the WD-40 ok for the o-rings? Also wouldn't just evaporate leaving no lubrication? I have been using that tacky oil that they charge a fortune for and I agree it just attracts crud.

yeah it does! :thumbsup:

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Is the WD-40 ok for the o-rings? Also wouldn't just evaporate leaving no lubrication? I have been using that tacky oil that they charge a fortune for and I agree it just attracts crud.

I have it on good source that it can work it's way behind the orings and screw up the grease that is in there protecting your chain.

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you should ignore the manual for this too. The recommended slack is the same they recommend for sportbikes with 4" of travel. The easiest way I have found to check the chain was recommended here by bronco or noble, dont remember which: 3 fingers tall on their side at the point where the chain slider ends on the top of the swingarm-like measuring Scotch on a Saturday night. It works out to about 3" of slack-about 60mm. You can run looser or a bit tighter.

Don't use tacky chain lube, it holds grit/dust in suspension, effectively creating a fine cut-polish which wears chains out very fast. I use wd40 and have for 20+years with excellent results and no down side.

You cannot keep power (torque actually) and gear taller. You have to give up one to get the other, that is the nature of mechanical advantage-it is like using a longer fishing rod, the speed will go up but the force will go down. I wouldn't run taller than stock 15/44. I have a 41 t rear sprocket I bought when the bike was new and I thought I wanted more top end but I have never put it on. I cant justify it and it would ruin the bike off road.

Chain: I go to a catalogue somewhere (online or at a dealer) and pick through until I find what I'm looking for. I go for the highest tensile strength and hardness (Reynolds number) I can find. I am currently running a DID chain listed for a gsxr1000. I think it will be able to handle the monster 400S :thumbsup:

I run 14/44 and cruise highways at 130km/h (that's around 80mph) and can pick my way through the woods and climb hills just fine.

4" of travel????? I never had sportbike that the manual said that..

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4" of travel????? I never had sportbike that the manual said that..

He was referring to the slack figure being the same on both the drz and a sportbike with a lot less, 4" in this case, of travel.

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What about the manuals' method for measuring chain stretch? Do you guys go with that when deciding if a chain is too far gone? :thumbsup:

The manual says count 21 pins (which is 20 pitch) and measure the distance between those 21 pins with a vernier caliper. If it is more than 319.4 mm (12.57 in.) it's toast.

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What about the manual's method for measuring chain stretch? Do you guys go with that when deciding if a chain is too far gone? :thumbsup:

The manual says count 21 pins (which is 20 pitch) and measure the distance between those 21 pins with a vernier caliper. If it is more than 319.4 mm (12.57 in.) it's toast.

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You don't have to use a caliper to measure the chain stetch.Besides, a dial caliper that measures over 12" is going to cost alot of money even if you can find one.A good steel machinist's rule is much more affordable and should do just fine to measure the stretch.Or you could use a common 6" dial caliper and steel rule together to do the measurement without breaking the bank.

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by vernier caliper he meant a machinists steel slide-ruler, not a dial caliper. I had never heard of measuring that way but it makes perfect sense. Dont know about the actual measurements though. I go by the side play. If the pins are worn there will be a lot of side ways flex. When new they dont have much. I usually have to replace my sprockets before my chain and have to replace the chain with them or the new sprockets will be worn prematurely by the partly stretched chain.

As for wd 40: there is a thread on here a few days old about it and how Tsubaki has been recommending it for decades. I dont know about it getting past o-rings and ruining grease, probably does, but if the rollers are ruined from the outside by dust in 10000km or from the inside by grease failure in 40000km is up to the individual owner.

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What about the manual's method for measuring chain stretch? Do you guys go with that when deciding if a chain is too far gone? :thumbsup:

The manual says count 21 pins (which is 20 pitch) and measure the distance between those 21 pins with a vernier caliper. If it is more than 319.4 mm (12.57 in.) it's toast.

Go to the back of your bike and lean down. Right at the back side of the drive sprocket grab the chain and pull. If you can pull it far enough to see between the chain and the U part of the teeth then your chain is stretched and needs to be replaced. That is a quick and dirty (literally) way to check for chain stretch.

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You don't have to use a caliper to measure the chain stetch.Besides, a dial caliper that measures over 12" is going to cost alot of money even if you can find one.A good steel machinist's rule is much more affordable and should do just fine to measure the stretch.Or you could use a common 6" dial caliper and steel rule together to do the measurement without breaking the bank.

I don't recall him saying "dial caliper", this kind will work fine though

caliperod1.jpg

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