sprocket problems!
 

Hey there, long time lurker first time poster! So it seems my hawk is a little, unique? maybe not and I've just not found the right thread. So I attempted to put on a 17-43 with an O ring chain and was met with utter failure. the 17 sprocket was causing the chain to grind on the INNER housing (engine side) so i dropped it down to a 16 and it was still grinding( pictures attached). I later realized the channel the locking plate goes into is on the inside instead of the outside? is this normal? took me a while to realize it, also having a big chain rubbing on tire issue, even with the 15-43, likely going to go back to 15-50 and see if i can use just the o-ring chain. anyone else seen this? see pictures, i reinstalled the 15 sprocket in the picture btw. thanks for your feedback!

also not sure if it makes any difference but this is the chain i got - 428HV - seems to be fine to me but I'm no chain expert! its 3mm thicker then the stock chain - measuring at 20.6 link end to link end, anyone know what the 428SO is measuring?

https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

https://lh3.googleusercontent.com/ra...4=w699-h932-no

So I slept on it and it struck me I can probably install the retainer first and slide the sprocket on, essentially reversing it and having the gear further out, not ideal but I'm thinking it will still hold on fine, thoughts?

I went from a 15 to a 17 tooth using the stock chain. I had to grind off a tab on the inside of the cover for it to fit back properly. that may be part of your problem. kind of a dumb question, but the chain is the same size, right?

Also, o-ring chains are substantially wider than a regular chain. I can't imagine there being issues with just swapping sprockets.

It's an oring chain so it is wider. Only problem I see is that the tab I would have to grind off is the engine side, not the cover as I've seen with others. Not exactly sure what's on the other side! As far as chain as I understand it's correct and it fits the sprockets just fine, but being oring it is wider.

Do you see the run mark on the left hand side on the engine cover? That's where it's hitting, not sure if grinding that are is a good idea?

i had no problem with putting the 17 on mine. had to wiggle the cover a little to get it to go back on but it went. i kept the stock chain. shim or a fender washer behind the sprocket might move it out to clear the wider chain.

I don't think you are seeing what I am referring to. Compare the sprocket location in this photo below to the one In my first post. Notice the one in my post the sprocket is to the inside and the one here is on the outside. I'm sure as new hawk owners purchase their 2016 bikes we will see more like this and a simple sprocket change isn't so simple anymore

http://hawk250.com/wp-content/upload...8-768x1024.jpg

clearly the output shaft is different in the two photos you posted. The first picture shows the sprocket mounted much deeper on the shaft (or the shaft is longer). Someone probably makes a dished sprocket.

The different output shafts is puzzling. I think this is more of a chain problem than a sprocket problem?

From what I have read, an o-ring chain isn't really needed on these bikes???

I just put new 17/45 sprockets on my hawk and a JT standard chain. My chain is rubbing slightly on the inside of the housing (engine side) like the original poster was talking about. My output shaft looks like the one in RAV007's first picture, with all of the shaft still showing.

Anyone have a solution?
I like the new gearing combo too much to switch back.

Has anyone looked at the chain's alignment?
If the two sprockets are on different planes, then the output shaft was likely mis-machined and this becomes a warranty issue.
But if the alignment is good, then the output shaft was likely revised to work with the rear wheel combo.

16t front 42t rear (2.63) should be a close enough ratio to the 17t front 45t rear (2.65) setup, the 16t should give you a little more clearance up front if that was your issue

You can also go with a 40 tooth on rear and keep the stock 15 on front. Close to the same gear ratio.

I rode the bike to work tonight, so I'll take the cover off again tomorrow and check to see how badly it scrubbed. There was some runout in the output shaft so hopefully it will not be as bad as I initially thought.

I will probably order a 16T sprocket anyway and maybe another rear in 42T.