Raptor Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
Just picked up 2011 125 for my son and would like to change front sprocket to a 13t. Does anybody know for sure if the front sprocket for a 250 will work on the 125? Having a hard time finding a 13t front sprocket for the 125.
 

·
Registered
Joined
·
178 Posts
Wow - 13! I'm running a 15 tooth on my daughter's 125 with good results. I don't see that the ignition is good enough to wind-up and run the higher rpms that a 13 tooth will bring. My daughter ran out of gear with the stock 14 and spun the tires too much. Then again we're running a Jason Wiedner built motor with tons of bottom-end power.

srxmiller is right, the ttr125 dirtbike sprockets are the ones to look for, ebay has a ton.
 

·
Registered
Joined
·
118 Posts
Hi Guys,

I really think gearing depends on engine design, tire size, track type and conditions. I gear for the longest straight on the track.

If I have a 400 yard straight, I don't want to run out of gear in 200 yards and if my longest straight is 200 yards, I don't want to be just clicking into 3rd at the end.

Each one of these examples I'm giving something away to the competiters and that is what I don't want to do.

CCD Howell: you are right, If you have a bottom to mid range motor, then gear it to work in that range, don't gear it to scream around the track if the engine isn't desiged for that. If you gear it to scream around the track, then your giving away the torgue and HP at which the engine is designed.

It is just like gearing a 2 stroke only a 4 stroke is more forgiving, 2 stroke you must keep it on the pipe, and that is where they make power.

Thanks,
Jason Weidner
 

·
Registered
Joined
·
23 Posts
My son ran his first cross country race, completely stock motor no pipe, I want to give him more pull in the woods what would you guys recommend for front sprocket size?
 

·
Registered
Joined
·
118 Posts
My son ran his first cross country race, completely stock motor no pipe, I want to give him more pull in the woods what would you guys recommend for front sprocket size?
You will want to either drop a tooth on the front or add teeth to the rear, either one will increase bottom end for the woods. You can drop a tooth in the front and still use your existing chain.

Thank
Jason
 

·
Registered
Joined
·
23 Posts
Thanks Jason, we ran Iron man this weekend my twin boys had so much fun, can't wait to get the raptor's torn apart and start on their woods weapon for next year!:)
 

·
Registered
Joined
·
144 Posts
I just ordered a couple 13 tooth drive sprockets off ebay today. We have a built motor and my son has never had to shift up into 5th on any of the MX tracks we have raced. So hopefully the more effective gear ratio will help get us around the track quicker.

I don't think you can use a Raptor 250 sprocket since they use a bigger chain.
 
1 - 13 of 13 Posts
Top