Yamaha YZF R125 Forums banner

Max Speed?

78905 Views 147 Replies 39 Participants Last post by  Wayne phillips
This is my first real bike, so my knowledge is pretty limited, especially when it comes to the mechanics..
Ive read numerous threads about the r125s top speed being 84ish mph, however mine simply refuses to go over 70?
She can do 0-60 with no effort, 60-70 takes a little time to tick up, then she simply stops, without coming close to red lining it.
Does anyone have any suggestions what I should be looking at?
1 - 20 of 148 Posts
Right, well it should definitely do more than that.

MOST important. Have you checked the oil level?????
Yeah, thats about all I have done tbf :(
Hmmm....

Have you tried tucking in?
Getting as low as you can?

Chain tension?
Is your air filter clean enough?

Have you tried loosing weight? ;)
(I'm joking about the last one...)
The way you accelerate is massively important, when going up the gear take it right up to 10,500 then change
The way you accelerate is massively important, when going up the gear take it right up to 10,500 then change
As you soon leant ;)
Ok, so there isnt an obvious mechanical problem then??

Im not small, Im well over 6ft, so I wont be doing any tucking on a 125, cos franky I think I'd look a twat :D
Im sure I read somewhere that weight is irrelevant, that you should still be able to get maximum speed out of a r125 even with a pillion, not sure ho true that is though.
But as I said, shes not red lining at 70mph, so shes got more to give from somewhere...
IanS said:
Ok, so there isnt an obvious mechanical problem then??

Im not small, Im well over 6ft, so I wont be doing any tucking on a 125, cos franky I think I'd look a twat :D
Im sure I read somewhere that weight is irrelevant, that you should still be able to get maximum speed out of a r125 even with a pillion, not sure ho true that is though.
But as I said, shes not red lining at 70mph, so shes got more to give from somewhere...
Weight is very important on these bikes, trust me i speak from experince!!
This is my first real bike, so my knowledge is pretty limited, especially when it comes to the mechanics..
Ive read numerous threads about the r125s top speed being 84ish mph, however mine simply refuses to go over 70?
She can do 0-60 with no effort, 60-70 takes a little time to tick up, then she simply stops, without coming close to red lining it.
Does anyone have any suggestions what I should be looking at?
Hi mate, firstly check your bike over/service it. Like would with a car make sure the mechanical side is all good.

Now the more important part.. If your looking to get top speed out of your bike your going to need a lot of space :D A road :) and you will need to let the revs build up closer to the red line. However I wouldn't advice doing 10.5k in every gear. Its not needed simply aim for about 9.7k up to your 3rd gear then as you feel the bike not moving up in the gear you will need to start red lining tuck your head in and look ahead at all times then once or twice look down at ya clock :)
Ok, so there isnt an obvious mechanical problem then??

Im not small, Im well over 6ft, so I wont be doing any tucking on a 125, cos franky I think I'd look a twat :D
Im sure I read somewhere that weight is irrelevant, that you should still be able to get maximum speed out of a r125 even with a pillion, not sure ho true that is though.
But as I said, shes not red lining at 70mph, so shes got more to give from somewhere...
then your changing gears too soon let it build up in lower gear
As you soon leant ;)
Yes I did yoda :p

IanS I'm 6"4/5, tucking in isnt too bad. Chest on the tank, toes up on the pegs, keep elbows and knees in. Sounds weird but try putting your arse right up against the pillion seat. Help streamline you abit more :)
  • Like
Reactions: 1
Yes I did yoda :p

IanS I'm 6"4/5, tucking in isnt too bad. Chest on the tank, toes up on the pegs, keep elbows and knees in. Sounds weird but try putting your arse right up against the pillion seat. Help streamline you abit more :)
LOL When I tuck in I think its quiet fun! I enjoy it rather than care what people think...
I have to try this in the morning see how fast I can go
LOL When I tuck in I think its quiet fun! I enjoy it rather than care what people think...
Yeah same! Only downside is a pain in your neck but I've done it so much it don't really affect me now ;P
I can promise you Im not, Ive a few long/empty roads near me, and Ive made a point of doing this, did coming home tonight infact. Tonight I didnt change gear until the bike started to shake, which is obviously too late if anything. Ive tried various different ways. but every time I flick up the last gear, the rev counter dips, and thats it, sticks at about 7-8k
If tucking your head in can account for 15mph then so be it, but i find that very hard to believe ;)
Well me being 'up' I've managed 76, down I can max it at 84 :)
Your speed's should be about 20 in 1st, 36 in 2nd, 52 in 3rd, 65 in 4th (needs verifying) 73 in 5th then max in 6th
  • Like
Reactions: 1
Your speed's should be about 20 in 1st, 36 in 2nd, 52 in 3rd, 65 in 4th (needs verifying) 73 in 5th then max in 6th
Yeah, check those speeds.
That will tell you if your gearing is still stock.

Unless you owned the bike from new, then in which case it will be! :p
Yeah, I'll take note of them when im out tomorrow, but they look about right to me.
Yeah, check those speeds.
That will tell you if your gearing is still stock.

Unless you owned the bike from new, then in which case it will be! :p
Yeah from new :)
1 - 20 of 148 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top