On my Gas Gas TXT 125 Pro i have a 9 tooth front sprocket (if i counted it correct) and what i think is a 46 rear sprocket. 

If i go for a 11 tooth front sprocket and a 49 tooth rear sprocket will i notice any differnce? 

I must say that i have a feeling that i will not notice any special differnce if i replace the front 9 tooth and rear 46 tooth sprockets with 11 t and 49 t sprockets or am i wrong? 

 

 

Edited May 13, 20242 yr by thesaint

Thats a big enough change. Its also making it higher geared, for a 125 that may no be the thing. Are you trying to make 1st taller? I think 9/48 was the hot setup back then for 125s

Edited May 13, 20242 yr by faussy

46/9 = 5.11

49/11 = 4.45

46/9 yields a higher gear reduction ratio than 49/11.

46/9 will yield more driving force at the rear wheel than 49/11 (for the same engine speed).

49/11 will yield higher ground speed than 46/9 (for the same engine speed).

 

Those sprocket combinations are nearly 15% different -- that will produce a very noticeable change.

2 hours ago, konrad said:

46/9 = 5.11

49/11 = 4.45

46/9 yields a higher gear reduction ratio than 49/11.

46/9 will yield more driving force at the rear wheel than 49/11 (for the same engine speed).

49/11 will yield higher ground speed than 46/9 (for the same engine speed).

 

Those sprocket combinations are nearly 15% different -- that will produce a very noticeable change.

I might try it if it will produce a noticeable change 😊 😊

If it is not the "big" thing on the 2005 TXT 125 Pro i can use the sprockets on my TXT 250 Pro 

Edited May 13, 20242 yr by thesaint

I would concur with faussy,  9 / 48 is the way to go on a 125 GasGas  

Below are the gearbox ratios of all GG Pro models.

1st, 2.996   

2nd, 2.571    

3rd, 2.187   

4th, 2.112   

5th, 1.125    

6th, 0.821

 

Below is the % change between those gears.

1-2, 16.5%

2-3, 17.6%

3-4, 3.6%

4-5, 88%

5-6, 37%

As you can see, a 15% change in overall gearing is significant -- almost like the difference between 2nd and 3rd.

You can also see that the difference between 3rd and 4th is not much by trials standards.  GG's patented "4 gear pairs provide 6 ratios" is pretty much a gimmick in my opinion.

 

Contrast this with the old GG TXT321 which had a conventional 6-speed gearbox (and was was ideal in my opinion). 

Below is the % change between those gears.

1-2, 16%

2-3, 27%

3-4, 28%

4-5, 57%

5-6, 50%

My 2 penny opinion on that combo:
try to use an uneven/even combo of gear numbers like uneven (like 11 teeth at the front sprocket) and even (like 48 to 50 teeth at the rear sprocket) or put a half link inbetween if gears.
The reason why is if you have on both gears with even or uneven numbers the chain links will not rotate on the gears and will produce more wear to the gears and the chain itself.

17 hours ago, pschrauber said:

My 2 penny opinion on that combo:
try to use an uneven/even combo of gear numbers like uneven (like 11 teeth at the front sprocket) and even (like 48 to 50 teeth at the rear sprocket) or put a half link inbetween if gears.
The reason why is if you have on both gears with even or uneven numbers the chain links will not rotate on the gears and will produce more wear to the gears and the chain itself.

It is this combo posted by agiow: 9 / 48 is the way to go on a 125 GasGas you are agree on right?

I have 9 / 46 on the bike right now so i do not think i woulld notice any difference going up to 49 or 50 rear sprocket 

 

Edited May 15, 20242 yr by thesaint