Sprocket change, chain too short? WTH?

[level41]

Stock the FZ has a 16t front, and 43t rear.
 
Recently I changed the front to a 17t, and it was a neat fit (within a millimeter tight) with the stock chain, moving the wheel all the way to the front.
 
Now I changed the rear from 43t to 38t. That's a 5tooth drop.
5 tooth, means 2.5 chain links need to be removed.
I removed 2 links from the chain, which means I SHOULD HAVE about .5 link (or a few millimeters) of chain play;
(not counting the chain play I get from Pythagoras’ theorem that the more the front sprocket has the same amount of teeth as the rear sprocket (and reverse), the more the chain length between the 2 sprockets will be the same as the distance between the sprockets; meaning, I get additional chain play from increasing the front or decreasing the rear sprockets)..
Anyway, 2 reasons I should have far more than just a few millimeters of play.
 
Well, as it turns out, I'm baffled to find I'm now 2mm short, and when I try stretching it, I am still 1 mm short of putting either the front sprocket on, or the rear wheel bolt in.
 
I don't understand, because by all means, the chain should have plenty of play, but definitely not short!
 
Anyone knows what's going on, and how to solve it?
 
One possibility might be the chain glider on the rear swingarm. It might actually be pushing the top part of the chain when not loaded; but I'm not sure this is the reason....
 

[r1limited]

Rule [HASH]1 Measure twice Cut once
 
You should have sized up the chain before you cut the links.  I am sure you know that now.
 
You resolve the issue by
[ol type=decimal][*]Buy a new chain and make sure you get a chain over the size limit
[*]You buy two links remove one link add three
[*]Either 1 or 2
[/ol]
 
 

[level41]

The math is cut 1 link for every 2 teeth less.
It should make total sense...
Seems like I was wrong...
 
I still have the 2 links of the original chain.
Breaking the chain is easy.
But pressing the tiny rod back in is the hard part, and requires a great deal of patience and luck, and tries, as the rods usually tend to misalign.

[r1limited]

Your tool box should never be without a breaker and press
https://www.motionpro.com/product/08-0470  Best one I have ever used
 
Also I carry with me always 2 master links, ya never know when the chain is going to snap.  Not sure where you are but if you were near me we can fix it.
 

[Beemer]

Your tool box should never be without a breaker and press https://www.motionpro.com/product/08-0470  Best one I have ever used
 
Also I carry with me always 2 master links, ya never know when the chain is going to snap.  Not sure where you are but if you were near me we can fix it.

In the other thread about pre ride check list you said you were anal. I'm sold. 

[faffi]

You can fit another half link plus an extra master if needed. But you are positive that if you hook the chain first over the sprockets, you cannot insert the axle? ANd you have set the adjusters for maximum clearance?

[r1limited]

Your tool box should never be without a breaker and press https://www.motionpro.com/product/08-0470  Best one I have ever used
 
Also I carry with me always 2 master links, ya never know when the chain is going to snap.  Not sure where you are but if you were near me we can fix it.

In the other thread about pre ride check list you said you were anal. I'm sold.

Live and learn.  Them damn Russians you never know when you need a link 

[peteinpa]

I hope you're getting NEW stake type master links to do this....
 
I can't believe you're gearing this SOOOO high. Just the front sprocket is + 6.5%. Your change is about 16% higher. Is that what you are doing really?
 
When the stock bike is doing 5k rpm it will now be doing 4200 rpm. That is more than a change from 5th to 6th gear.
 
As far as the chain length....There are no theorems involved. it's strictly tooth count. Since you can't remove 1 link and rejoin (they used to make 1/2 links) the chain you must remove 2 links. (an inner and outer)
 
If you removed 1 inner and 1 outer link you should be good. Something else is preventing you from reassembly.
 
When I did the plus 1 on the front I was nowhere near having the rear wheel all the way forward.

[level41]

I do have a chainbreaker tool, and use this to press the rods back into the chain.
It works for the most parts, but mostly for smaller chains than this.
 
I have gained some valuable insight, that I want to share with you all.
 
1, if you want to have taller gears, you first and foremost change the front sprocket to a 17t. Don't change the rear (see [HASH]3 why). On the chain type used, a 17t front is the largest you'll be able to find, but an 18t might fit (should you find it) with the removal of the chain glider (plastic protection over the chain). The 17t does not need a different chain.
 
2, Once you have done the front, you can reduce the rear by 2t to 3t at most (to 40t) on a stock chain. Any smaller rear sprocket, and you'll be beyond the furthest adjustment on the wheel, and have too much chain slack.
 
3, If you want any larger adjustment than a 17t front, and a 40t rear, you'll have to remove the chain glider that protects your swingarm (not recommended).
You can go down to a 38t, but the rear always will need to be loaded. If you move the bike around without load, the swingarm will get in the way of the chain.
This is also the reason a 17t front is necessary, because without it, there will be clearance issues.
 
Below is a picture of a 17t with 38t rear, with the chain glider in place:
 

 
The image is taken with my cellphone, so there's a bit of an exagerated fisheye lense effect, that makes it appear as if the chain and broomstick are warped or bent, however this is not the case.
As you can see when the bike is not loaded, around mid-chain, the glider pushes the chain up. This might be less of an issue when you're on the bike however, I'd advise against pushing your bike forwards. It'll wreck the glider.

[level41]

Now, the next part,
 
I tried pressing the rods back into the chain but was unsuccessful. I wasted all my rubber o rings, or x rings, or whatever it was, they're all damaged.
 
Now, I'm contemplating on getting a proper press, or just buy a new chain.
The new chains can easily be pressed with a chain breaker, because I don't have to press the rods, but  press  the metal connection plate, which is a lot easier to do!
 
The stock chain is a 525 x 108 links.
I need a 525 x 106 links.
I found 3 types of chains:
 
A $30 7700lbs tensile strength o-ring chain from Malaysia (supposedly using Japanese steel):
https://www.amazon.com/gp/aw/d/B00BV6WBA4
 
A $66 8500LBS X-ring chain from Japan:
https://www.amazon.com/gp/aw/d/B004XAX7FI
 
Or, A $68 10600 LBS heavy duty x-ring chain from Thailand:
https://www.amazon.com/gp/aw/d/B00DX8CBN0
 
I think the heavy duty is overkill.
I'm just concerned about the tensile strength of the $30 chain, if it'll be enough?
Anyone knows the tensile strength of the stock chain?
 
Since I'm running a 17t front, the chain should handle about 6% less pull, than stock.

[r1limited]

Is that freakin rust on that chain?
Are you packing it with grease as well?
 
Man that is one mucked up chain.

[r1limited]

Level41
 
I mean no disrespect at all, what I am gathering from the post to now is you pretty much butchered the chain. From the photos IMO it appears this chain is in need of replacment as I do see rust. Your cleaning and maintenance of this chain is clear too there is a boat load of crap clearly visible on that chain. I want to give you some pointers to help.
1: Clean and grease often (The best cain cleaner I have found is Maxima chain cleanup and Amsoil MP HD for chain lube)
2: Invest in a good chain brush
3: It takes 15 minutes to clean a chain in the bike (1 hour for a good brushing off the bike)
4: A chain is not a chain is not a chain, get a good chain Vortex has a good supply and is a reputable company, Renthal, DID, Diamond all good just dont go cheap.

[gregjet]

PS : DON"T use petrol to clean a chain with seals ( xring, O ring etc). The petrol will screw up the seals and they will disintegrate. Citronella oil and or kerosene will be OK. Citronella oil will make youi bike smell wierd but it is amazing gunk cleaner.
BTW you chain length should be checked at the spot where the CS sprocket centre, swingarm axle and the axle are in a line. That's where the chain has to be the longest. That's LENGTH check not tension check.

[level41]

The bike is standing outside. What you see is only superficial, the kind that grows here in a week or two of not riding,
The chain is perfectly fine. I use lithium grease. It's a dry type of grease that only sticks in the rings.

[level41]

From the charts that i've seen, a I need between 7000 and 10.000 LBS tensile strength.
7000LBS being minimum, and 10.000 for racing purposes.
 
The ratings for a 9500 LBS chain are up to 140HP; and since the FZ is low in HP (only 75), I think that the 8600LBS chain will do just fine.
The cheaper chain ($30) would have as well.

[norcal616]

525 chains are over kill for this bike in my book, 520 chain/sprockets have a far better ranges of sizes on hand and available at most powersport stores I know of and cheaper...If a new R1 has a 520 chain, its plenty for the little FZ-07... When my stock chain/sprocket are junk, its gonna get a 520 setup...

[YZEtc]

The part that gets my attention is about "pressing the tiny rods back in".
Can you explain in detail what you are trying to do with this step?

[peteinpa]

You CAN NOT break a chain and then reuse those parts to re-assemble. You must buy a rivet link made for this use.
 
At this point you must buy a new, quality X-ring chain and install it correctly.
 
 

[faffi]

You can use undamaged links, but need a proper master link to connect the bit, meaning you will end up with two master links instead of one. As petinpa said, you cannot use a standard link as a master link.

[peteinpa]

Don't use a clip type master link either. I wouldn't even use one on a Grom.
 
For general knowledge of how to change chains and sprockets check this video from Motorcyclist:

 
If you are replacing a worn chain save your rivet tool from wear and tear. Just use a cut off wheel in your dremmel and cut through both side plates. It's very fast.

[DewMan]

I've seen several suggestions to use a cut off wheel to remove an old chain to be replaced. Which is a good idea if you're replacing the front sprocket while you're at it.
 
I'm of a differing opinion if you're NOT replacing the front sprocket and suggest pressing out the link of the old chain to leave an open link in the old chain enabling you to use the backing plate with pins of a master link to "link" the old and the new chain together temporarily to use the old chain to pull the new chain through the front sprocket with the bike in Neutral.
 
I keep an old clip style master link in my tool box for just such times. This allows replacing the chain without having to pull the sprocket cover saving time & effort.
I've not experienced any issue using this method, but if you see an issue doing it this way I'm always open to hearing it.

[level41]

The rivets that you extract, you can press them in again with the chain breaker tool.
Some chain breaker tools actually have parts that allow you to do that.
Mine doesn't; so pressing the rivet back in the chain, is a tedious job; because it has to be aligned perfectly.
It works ok for 520 chains, but 525 of the Yamaha, has an increased pressure on the rivets, and the chain is wider too.
 
You don't need a master link, as long as the rivets are properly re-inserted.
Reinserting an old rivet is not an issue, unless the chain plates are damaged; which is very unusual.
The lateral forces the rivets experience, is very low, so they won't fall out.
Been doing this for ages, and many of my bikes went through several tens of thousands of miles, and get replaced when the steel front sprocket gets replaced (they usually outlast 2 aluminum rear sprockets).
 
The chain breaker tool can put so much pressure on the rivets, that it seals them off again at the edges that stick out of the chain plates.
 
a 520 chain is a lot easier to handle.
I would have loved to see someone swap their chain and sprockets with a 520, and let us know what the largest front sprocket would be (since the 520 chain gives you a little more clearance, I wonder if an 18t up front would fit fine?)

[pattonme]

Next time use this site and it'll save you a ton of grief.
http://www.gearingcommander.com/
 
And no, @level41 an 18 isn't going to fit. 17-41 is probably possible. You don't want the sprockets to be an clean multiple of each other, either. For even better fuel mileage turn your crank around and spin it the other direction.  P-)

[level41]

sigh...
I wonder if you used it yourself?
 
I know gearingcommander, and it basically tells the same tale.
+1t front -5t rear = -4 tooth, or -2 links.
 
Stock: 16 F + 43 R with a 108 link = 24.38" distance
modified: 17 F + 38 R with a 106 link = 24.44" distance (a full 0.06" more chain slack), yet in practice this is not the case.
 
And the 18t was referring to a 520 sprocket swap, not for the stock 525 sprocket/chain.

[r1limited]

The rivets that you extract, you can press them in again with the chain breaker tool.  

WRONG whoever taught you or told you this is WRONG!.  Buy a few rivit links as well as master links to keep around.  I am assuming you have never experianced a chain brake and it wraps around you counter or rear locking things up.  When it comes to your bike, dont F**King be cheap, do it right, your life depends on it. 
Sorry but some of the stuff I have been reading, is like listening to the night news and the bullshit spitting out.  Please find someone that will teach you proper maintenance.