That's interesting Mike. All US riders have reported that their speedo's are more or less accurate, that is until you said this (you are in the US, aren't you?). Mine's about 10% optimistic, according to my sat nav, which I trust more than my speedo. I'd rather mine was accurate. In my view, it has safety implications. Over here, if you do 27 mph in a 30 mph zone, you'll be holding the traffic up, and constantly have people tailgating you, and trying to overtake you, even when it's not safe to do so. I compensate for this by doing 33 mph on the speedo, but those that don't know, and are trying not to speed, are putting themselves in unnecessary danger.Mine isn't.
I have installed 15T for CBR 250, the metal guard needs to be removed. Now the bike is different.Nice photos. The same procedure applies to fitting a 15T front sprocket with the additional step of trimming the nubs from the plastic sprocket cover so that the metal guard piece can be positioned all the way forward against the bolt holes to make sure it doesn't rub.
Actually the speedometer and odometer both operate from the same signal coming from the speed sensor in the gearbox. Any sprocket size changes will affect both meters.I just clicked "Buy Now" on a 13T Renthal... Let the games begin!!
Now I don't plan on purchasing a speed labs dr thing because I'm used to an off-speedo, but can anyone confirm that the mileage/odo will still be accurate? I'm guessing that the speedo and odo are measured differently but haven't read anything confirming this yet.
If your goal is a ratio close to 2.850 it would make more sense to go with 14/40 (which is actually 2.857) rather than a 13/37 (2.846), as you are only having to change the rear sprocket. From what I've seen, the only aftermarket rear sprockets that are currently available for the CBR250R are made of aluminum so they are lighter, but at the expense of shorter service life. I haven't seen any steel aftermarket rear sprockets available for this bike.So i know there's lots of talk about the ratio.
so the ratio for 13/37 = 2.85
and the ratio for 14/40 = 2.84
my question is does the size of the actual sprockets matter or do you really care about the ratio. Is there any real difference between the 2 set up? The only thing i can think of is it's 'less' weight. Hopefully this makes sense
I guess from that statement the 13/37 should have the slightest higher top speed from my understandingOne more thing to consider is that the average rider will not notice a huge difference between a 14/40 (2.857) and a 13/38 (2.923) set up as far as typical riding goes... the 13/38 ratio will have a slightly lower top end speed.
Kind of a tough question, considering that your chain & sprocket set are about mid way through their lifespan at 9500 miles.Thinking about changing to the 13T sprocket. With 9,500 miles on the bike am I going to have to get new chain and rear sprockets? When changing sprockets on a bicycle you have to change both.
Did you try flipping the retainer plate over?... the bolt holes on the plate will only line up with the sprocket holes from one side of the plate.Unfortunately my experience with the J.T. sprocket from Motorcycle superstore yielded nothing but frustration. The retainer holes on the sprocket did not align with the stock retainer plate. The sprocket fit the spline like a glove but the retainer plate holes were too wide. Seems like they would pair the retainer plate with this sprocket. I noticed a touch of later play in my 14t sprocket. Bike ran fine after putting it back together. But it took a few tries to the get the stock sprocket back and the plate aligned.
What JT part number is on the sprocket?Yes, tried flipping it over. I aligned the sprockets atop one another. With the spline center teeth aligned, the plate holes on JT sprocket do not align with the stock sprocket. Too far apart.