Top speed

[Shawn Clark]

Ok guys I’m sure this gets asked a lot but I’m just curious as to if my bike is running at normal speed as far as top speed!  I have a KX125 that I put quite a bit of work in and I feel like I’ve gotten it close to as good as it’s gonna get.  With that being said my top speed today and this was just after I got it warmed up was 67mph may have been able to get a little more but ran out of road!  So I would say around the 70mph Mark is where I’m at.  Let me know what you guys think and how fast is normal for these bikes?

[Drop-Bear]

13 minutes ago, Shawn Clark said:

Ok guys I’m sure this gets asked a lot but I’m just curious as to if my bike is running at normal speed as far as top speed!  I have a KX125 that I put quite a bit of work in and I feel like I’ve gotten it close to as good as it’s gonna get.  With that being said my top speed today and this was just after I got it warmed up was 67mph may have been able to get a little more but ran out of road!  So I would say around the 70mph Mark is where I’m at.  Let me know what you guys think and how fast is normal for these bikes?

depends on the gearing

[DroppinDeuces]

13 minutes ago, Drop-Bear said:

depends on the gearing

In MX it's not top speed that matters. It's getting "there" first, whether that's a corner or the end of a whoop section. More often than not, that has more to do with rider ability and bike set- up.

Edited March 8, 2020 by 00boob

[Smoking 2's]

Fast in a straight line is easy! Couple custom sprockets and a down hill start and 150 should be easy but then what!

[bradje]

Shawn, how did you measure your top speed? I only ask as 70mph on a MX bike is not usual. My yz250 2 stroke was right around the 62mph mark and afaik that is about  average for moto bikes with the gearing used on MX tracks.  Perhaps yours is gearing for more speed?

[Drop-Bear]

2 minutes ago, bradje said:

Shawn, how did you measure your top speed? I only ask as 70mph on a MX bike is not usual. My yz250 2 stroke was right around the 62mph mark and afaik that is about  average for moto bikes with the gearing used on MX tracks.  Perhaps yours is gearing for more speed?

Are the KX 125's a 5 speed, or 6 ?

The top speed on my RM 125 is typically faster than that of a 5 speed YZ250.

Edited March 8, 2020 by Drop-Bear

[Shawn Clark]

 

Just now, bradje said:

Shawn, how did you measure your top speed? I only ask as 70mph on a MX bike is not usual. My yz250 2 stroke was right around the 62mph mark and afaik that is about  average for moto bikes with the gearing used on MX tracks.  Perhaps yours is gearing for more speed?

My gearing is for more speed..I was clocked with a radar..I’m about to drop my front sprocket to a 12 from a 13...and I have 48 on the rear

1 minute ago, Drop-Bear said:

Are the KX 125's a 5 speed, or 6 ?

6

[Drop-Bear]

5 minutes ago, Shawn Clark said:

 

My gearing is for more speed..I was clocked with a radar..I’m about to drop my front sprocket to a 12 from a 13...and I have 48 on the rear

6

Larger sprocket on the front means the engine doesn't work as hard. Change the rear sprocket.

Don't ask me to explain, I have the flu atm and can't remember the explanation anyway. But, Its commonly known in Kart racing.

Edited March 8, 2020 by Drop-Bear

[bradje]

37 minutes ago, Drop-Bear said:

Are the KX 125's a 5 speed, or 6 ?

The top speed on my RM 125 is typically faster than that of a 5 speed YZ250.

Bear, fly my freezing ass down to Australia and we can do some testing for TT

[Drop-Bear]

5 minutes ago, bradje said:

Bear, fly my freezing ass down to Australia and we can do some testing for TT

13/51, and just hold it on .

125's are made to thrash/rev.

[Pigsfly]

I can see a post coming. Why did my bike explode 80mph

Edited March 8, 2020 by CRJohnny

[piltoyougram]

I think we all missed the main point of this conversation. Shawn Clark is trying to figure out what the top speed of his 2smoker will be before it becomes toast?!