My 15t sprocket change w/pics!

ctr46 · 07-15-2008, 07:55 AM

Ok so I decided to go ahead and do the (-1) 15 sprocket change. I did have my concerns as to whether I would be mechanically fit to do it but after reading all about it here at SBN I decided to take the plunge and go ahead.

I got my sprocket from the local yammi shop and it was a steel sprocket from JT sprockets… Cost me just under 40 dollars here in Norway.

Ok this is how I did it…
Hmm I didn't note down the tools needed but I'll try to remember...
The three cover bolts was torx,
Rear axle bolt 32mm (in your bike's toolkit, I used my own tools...)
Sprocket nut was either 32mm or 30mm think it was 32mm but can't remember.
To adjust locknut/adjuster nut just use the tools in your bike toolkit.

First here is a photo of the workplace ready…
IMG_0113.jpg

Ok remove the three bolts marked in red. On my bike I had to loosen the bellypan to get access to the last bolt. You are able to remove the cover after fiddling with it. Can be kind of tricky but just wriggle it out and take your time...
IMG_0114.jpg

This is what you see underneath. Notice the layer of road debree and dirt under and to the left of the chain!!!
IMG_0116.jpg

Here is a closer look at the sprocket and the washer bent to keep the bolt from turning...
IMG_0118.jpg

Here I have bent the washer back so I can get the bolt off to change the sprocket...
IMG_0119.jpg

ctr46 · 07-15-2008, 07:58 AM

Now loosen the rear axle...
IMG_0120.jpg

And loosen the locknut (on both sides naturally!)
IMG_0121.jpg

Move both adjuster and locknut all the way to the back (both sides!!)... Now you should be able to push the wheel further forward (towards front of bike) to get the chain slack needed to change the sprocket...
IMG_0122.jpg

Remove old sprocket...
IMG_0123.jpg

See the difference...
IMG_0124.jpg

ctr46 · 07-15-2008, 08:00 AM

Insert new sprocket... Tighten the bolt... I bent the washer back around the bolt to keep it from turning loose... Just use some pliars for that... It did take some force to bend the washer around...
IMG_0125.jpg

Reassemble bike and make sure you adjust chain slack to account for the new smaller sprocket and you're done... I did clean the area around the front sprocket while I had it open since it was so filty. Just removed the worst bit... And for the swingarm on the chain side... I took the back cover off and cleaned some inside since I had a bit of a hard time getting the adjuster nut further forward when adjusting the chain. It was so filthy that it was hard to adjust but after some cleaning it worked like a charm. WD-40 is my best friend

IMG_0127.jpg

Ok I did have to spend some time adjusting the chain but that was merely bacause I had never done it before... It was fun getting to know my bike a bit more! Now I'm hoping that my speedohealer will arrive in the morning...

Now after using the bike for a little while after the change all I can say is DAAAAAMN!!! WOOW what a difference!!! The most welcomed difference was the MUCH smoother gear shifting!! It still clunks a little from 1st-2nd but compared to before it's nothing... The gear shfting is so smooth now I'm wondering why yammi didn't make 15t sprockets factory for the fz6...

As for the power increase I will have to agree with others here that the bike pulls harder and feels stronger. As for wheelies it doesn't make the front too light... you have to want to wheelie to do it... but it's easier now than before... I have never done a wheelie before and can't really tell you guys much about it. However yesterday testing out the new power I actually tried to wheelie and well it came with no problems...

But wheelies isn't my thing and I'll leave that to the people who can do them and want to do them

Hope this was helpful and more people will do the sprocket change...

DefyInertia · 07-15-2008, 09:40 AM

Nice write up. I'm sure this will make the decision for a lot of people a little easier.

I believe most would suggest that the lock-washer be replaced....similar to a crush washer.

WhisperQuiet · 07-15-2008, 09:47 AM

son of a bitch...i think i'm ready now to pull my engine.

Donnie869 · 07-15-2008, 09:50 AM

Again, Good write up.

Needs to be stickied in the " How To " thread.

rg-one · 07-15-2008, 10:24 AM

Quote:

Originally Posted by WhisperQuiet

son of a bitch...i think i'm ready now to pull my engine.

throw some hi-comp pistons in there and titanium valves, hell bore it out to 650cc and but a blower on it

CrazyBiker · 07-15-2008, 10:47 AM

Nice writeup. Man, that lock nut is rusted. It seems it rains a lot there. This along with the other long thread by Para needs to be STICKIED!

PETSHOPBOY · 07-15-2008, 11:00 AM

Good Job,what brand of socket wrench is on your axle nut??

ctr46 · 07-15-2008, 11:40 AM

Quote:

Originally Posted by PETSHOPBOY

Good Job,what brand of socket wrench is on your axle nut??

Defy - Thanks!

Yeah i was hoping this would make more people want to do the change and feel the difference. +1 on the replacement lock washer hehe... Just didn't know the condition of it before I pulled the cover off and then it was too late.. Will look into getting it replaced at a later time... maybe.. nobody will see it behind there anyway so I might just leave like it is...

Donnie - Thanks

yeah we'll see if any of the moderators like my writeup hehe...

Rg-one - Well that would probably be nice, but since I'm far from a mechanic I'll leave my bike as is hehe...

Crazybiker - thanks! I'm happy with the mod and it wasn't really as hard as I maybe thought it would be. Yeah my bike has been running in a LOT of rain the past year... So I guess the rust on that bolt wasn't too much of a surprise

I'm hoping my thread will make others more confident in doing the mod since it does make quite a difference... As some others have posted the only thing I've noticed is a slight increase in chain noise due to the lack of the rubber surrounding the sprocket compared to the old one...

Petshopboy - Hmm I'm not really sure... I bought the tools as a set... I could run out and look.... ok here... Hmm it doesn't say anything on the box. All it says on the tools is "72 teeth Professional CR-V". The whole box cost around 140 dollars I think...

jdager · 07-15-2008, 01:18 PM

ctr46, thanks for the nice writeup, I just went and ordered a new sprocket due soley to this. thanks again

ctr46 · 07-15-2008, 01:29 PM

Quote:

Originally Posted by jdager

ctr46, thanks for the nice writeup, I just went and ordered a new sprocket due soley to this. thanks again

Cool, my pleasure!!

wavex · 07-15-2008, 02:14 PM

Nice!

Ask Killer to add it to the "Topics Worth Linking" thread in the sticky section.

ctr46 · 07-15-2008, 02:48 PM

Quote:

Originally Posted by wavex

Nice!

Ask Killer to add it to the "Topics Worth Linking" thread in the sticky section.

Thanks!

Yeah I'll pm him if he doesn't see it for himself...

MacBandit · 07-16-2008, 09:22 AM

How would changing a a tooth on sprocket have any affect whatsoever on how smooth a bike shifts? The only thing I can imagine is that you are being forced to shift at a higher RPM now which would lead to smoother shifts.