Chain broke while riding- sprocket help needed

[Dj9384]

Hey guys,

I was riding yesterday and the chain on my 2010 250r snapped. Luckily I was just pulling out from a stop sign so I didn't fall or anything but now I have to replace it. I've watched a few videos on how to replace the chain and sprockets and the ones I've seen say to hold the back brake to get the front sprocket off, but since I have no chain, this won't work. Any ideas how I might remove the front sprocket? Also what are people's suggestions for sprocket sizes? Do differing sizes affect performance by much?

Thanks

[kashun84]

remove it with your new chain on. 15T CS sprocket is a good place to start with and it's really depends on your riding style. I do 100% highway riding and I am aiming for lowest RPM at highway speed, 15/38 setup treat me well but it might be too long for another rider. http://www.gearingcommander.com/ is a good place to play around your gearing.

[CajunNinjaR]

You couldn't use the broken chain? If your holding the back brake it can't spin around to the broken spot. So just run it from the top of the rear sprocket to the front one? If the nut spins clock wise you will have to loop it under. Not sure which way the nut on the front sprocket has to spin and I can't seem to do a search on my mobile...
Posted via Mobile Device

[DmbShn41]

A worthwhile investment is an impact wrench, 1/2" drive. Picked one up at Harbor Freight for $40. Using this with a quick trigger finger will release that nut. Make sure it's properly torqued when reinstalling.

[cbinker]

impact guns work wonders on sprocket removal.

[Dj9384]

Thanks for the quick responses! I'm going to try using the broken chain only because I'm stuck at home until I get a ride to the store from a friend. If not I'll try to get my hands on an impact gun. I'm going to play around with these sprocket combinations. Thanks again guys!

[CZroe]

I used their "Emergency 12v Impact Wrench" that was $24 after coupon (same 20% off coupon they have everywhere). It worked beautifully. That one was particularly useful because I had no air compressor and couldn't work near an electrical outlet (connect it to the bike's battery).

Make sure to get the right-sized impact socket (can't recall)!

[alex.s]

harbor freight, electric impact gun, $25

[CZroe]

Originally Posted by alex.s

harbor freight, electric impact gun, $25

Are you talking about the ones that take a battery pack or the ones that connect to your bike's battery? The $30 ones that are normally $25 after coupon and the emergency 12v one are all on sale right now for $16 after coupon.

I still like the emergency 12v one because it's good enough for our bikes and there's nothing else to buy besides metric impact sockets (of course). The included SAE sockets are worthless for our bikes but they came in handy for changing car tires recently, so it is another positive attribute for the 12v emergency one.

If you get hex socket adapters for other jobs make sure to get the long ones. Almost everything that has needed them has needed the longer ones (reaching the fork oil drain bolts, for example).

[alex.s]

i use a big orange one that plugs into a wall

[CZroe]

Originally Posted by alex.s

i use a big orange one that plugs into a wall

Ah. I think it's a bit more expensive than that. The two I can find are both on sale for $50, $40 after coupon (normally $70).

I was interested since the "Emergency" 12v one may not be designed for long-term use and has lower specs, but they probably describe it as "Emergency" because it's intended to be kept in your trunk for "Emergency" situations (roadside tire changes). That's also why it comes in a plastic case.

[Motofool]

Originally Posted by Dj9384

Hey guys,

I was riding yesterday and the chain on my 2010 250r snapped. Luckily I was just pulling out from a stop sign so I didn't fall or anything but now I have to replace it.........

Welcome to Ninjette.org, Dave !!!

What will prevent the next chain from snapping?

It is possible that your current chain and sprockets are perfectly fine, needing only a decent riveted master link.

[reroka]

Per this website the current set I have I should be at 76 MPH at 8800 rpm
My set up is a 14/43 and right now I am at between 65 and 70 at 8800rpm

So something is messed up. I am going to a 14/42 to drop it some more but I dubt it will drop much.

Originally Posted by kashun84

remove it with your new chain on. 15T CS sprocket is a good place to start with and it's really depends on your riding style. I do 100% highway riding and I am aiming for lowest RPM at highway speed, 15/38 setup treat me well but it might be too long for another rider. http://www.gearingcommander.com/ is a good place to play around your gearing.

[DmbShn41]

Originally Posted by reroka

Per this website the current set I have I should be at 76 MPH at 8800 rpm
My set up is a 14/43 and right now I am at between 65 and 70 at 8800rpm

So something is messed up. I am going to a 14/42 to drop it some more but I dubt it will drop much.

Are you using your stock speedometer to reference the speed? Ninja 250 is notoriously known for over stating the speed.

[Alex]

The error on both the tach and speedo themselves can be significant. You can calculate what it actually is right from the gear ratios (use www.gearingcommander.com to tweak at will), regardless of what the gauges are telling you.

[reroka]

Yes That is all I have to go by. I am on the Highway going 65 70 and I am around 9000rpms even though I am a 14/43 it much less than the stock 14/45 but I am going to go to a 14/42 to see if that lowers it a bit more. Since I ride on the highway a lot it seems I burn through gas faster.

Originally Posted by DmbShn41

Are you using your stock speedometer to reference the speed? Ninja 250 is notoriously known for over stating the speed.

[mgentz]

At least my odometer is dead on.