Rear Sprocket contour ??

Bill Hilly · 03-26-2021, 04:18 PM

I got my JT 42 tooth rear sprocket it the mail the other day, but just installed it earlier today on my Brozz 250, and it is more of a flat shape ,as opposed to the factory sprocket's slightly dish shape. I went ahead, and installed everything, and took a short ride of about 3 miles, and according to GPS my top speed was 59. Everything felt smooth, and I heard no odd noises. I know this is the go to replacement brand for Chinese bikes, but do you think I may have got the wrong sprocket ?, Or am I good to go ?

idle_purr · 03-26-2021, 06:09 PM

If all is smooth and seems normal you should be fine. The snap ring seemed good? Everything locked back in tight? Are the tires getting fuel? Do they have spark? Okay, just kidding on the last two questions.

Bill Hilly · 03-26-2021, 06:22 PM

Yeah, The clip is secure, and it is functioning smoothly. I guess if one were to measure it the chain would be just about a quarter inch inward with the flat sprocket.

Megadan · 03-26-2021, 07:39 PM

Quote:

Originally Posted by Bill Hilly

Yeah, The clip is secure, and it is functioning smoothly. I guess if one were to measure it the chain would be just about a quarter inch inward with the flat sprocket.

And that is about the same offset as the TT250 sprocket. It won't hurt anything. On the TT250 the sprocket bolts to the hub directly so you can use 5mm spacers to compensate if so desired.

gwowzer · 03-26-2021, 10:41 PM

It's funny I just pulled up the forum after finishing putting on a 43 tooth rear, and had thoughts about the stock dished sprocket vs the flat JT.
There is another pretty recent thread where washers were used under the front sprocket to space it a little.
I was worried I was going to have to go on a washer hunt down at the hardware store.
But honestly, after putting the flat sprocket on, I think it lines up better than the stock sprocket did on my bike.
I used a long straightedge and a motion pro tool and it really does look like it lined up better.

03-26-2021, 04:18 PM	#1
Bill Hilly Join Date: Feb 2021 Posts: 948	Rear Sprocket contour ?? I got my JT 42 tooth rear sprocket it the mail the other day, but just installed it earlier today on my Brozz 250, and it is more of a flat shape ,as opposed to the factory sprocket's slightly dish shape. I went ahead, and installed everything, and took a short ride of about 3 miles, and according to GPS my top speed was 59. Everything felt smooth, and I heard no odd noises. I know this is the go to replacement brand for Chinese bikes, but do you think I may have got the wrong sprocket ?, Or am I good to go ?
	0

03-26-2021, 06:09 PM	#2
idle_purr Join Date: Feb 2021 Location: NY Posts: 218	If all is smooth and seems normal you should be fine. The snap ring seemed good? Everything locked back in tight? Are the tires getting fuel? Do they have spark? Okay, just kidding on the last two questions. __________________ NO HILL TOO STEEP NO MUD TOO DEEP The Brozz \| The Hawk Upgrades, Accessories, Etc... Assembly Checklist: Brozz 250 \| Hawk 250 ~idle_purr
	1

03-26-2021, 06:22 PM	#3
Bill Hilly Join Date: Feb 2021 Posts: 948	Yeah, The clip is secure, and it is functioning smoothly. I guess if one were to measure it the chain would be just about a quarter inch inward with the flat sprocket.
	1

03-26-2021, 10:41 PM	#5
gwowzer Join Date: Aug 2019 Location: Central Ohio Posts: 297	It's funny I just pulled up the forum after finishing putting on a 43 tooth rear, and had thoughts about the stock dished sprocket vs the flat JT. There is another pretty recent thread where washers were used under the front sprocket to space it a little. I was worried I was going to have to go on a washer hunt down at the hardware store. But honestly, after putting the flat sprocket on, I think it lines up better than the stock sprocket did on my bike. I used a long straightedge and a motion pro tool and it really does look like it lined up better.
	1