Sprocket Combination

[asistech]

I would like to try riding at the local track. I'm woundering what is the best combination for the front and rear sprocket. The track is very technical with 4 table tops, 2 double and a triple jump, berms and few sharps conners.
I did come across a table for sprockets combinations but could not remember which sites. Can anyone help?

 

[MattR]

I did come across a table for sprockets combinations but could not remember which sites. Can anyone help?

Here's the sprocket table that I posted:
http://www.gasgasrider.org/forum/showthread.php?t=212

 

[asistech]

That really helps. But i'd like to know the different between using
12 Front 48 Rear and 13 Front 52 Rear. The ratio are both same 4.0 .
Thanks again MattR.

 

[JoshP]

"That really helps. But i'd like to know the different between using
12 Front 48 Rear and 13 Front 52 Rear. The ratio are both same 4.0"

The biggest difference I have found with a 12 front instead of a 13 front with a larger rear was chain wear. I tried a 12 tooth on the old KDX and killed the chain quick, switch right to a 13 with a 50 in the rear and had no more chain wear issues. But this is just from my experience. Hope it helps.

 

[Berkyboy]

The ratios you have chosen are identical but like JoshP said a 13 tooth front sprocket will wear longer and be easier on the chain.

What you need to keep in mind is that GasGas uses a 48 tooth rear sprocket on all of their bikes just to save money. For the EC200s and MC250s they use a 12 tooth coutershft sprocket to match the engines power characteristics with the most likely terrain the bike will be ridden in. With the EC 250s and 300s they go with a 13 tooth sprocket.

Keep in mind that if you go to 13:52 your existing chain is going to move your rear axle forward so you should buy both sprockets and a new chain at the same time and consider adding a couple of links to keep the axle in a middle position in the swing arm.

The biggest thing is you need to evaluate the present gearing that you have have and then make a choice on what gearing would suit you better. What I would do is buy a 13 tooth sprocket and use it with you present rear sprocket and then compare the two different ratios (1:4 compared to 1:3.69) and see what seems to fit your riding style better. Then make your rear sprocket choice based on that test.

 

[asistech]

Sprocket Combinaation

Thanks, i'll try those options.

 

[Hawkeye]

13/52 seems to work well for tighter mx tracks from my experience. I have 6 or 7 Gassers out on my .9 mile long mx track and most are running between 13/50 and 13/52 for gearing, most are 300's, but we have one 200 out there with the lower gearing. You may find that the bike turns better and quicker with the shorter wheelbase with 13/52 and the stock chain.

My track has a lot of doubles and tables, the longest one is 32 feet, but with my new YZ and my 300 GG plans are underway for a 50' tabletop. Need more of a challenge!

 

[zero_chances]

I don't ride tracks much, but my 13 front, and 50 rear seem to work well with the power on my GG 250. But remember to get a slightly longer chain when you get bigger sprockets, so you can keep a good amount of ajustment in your axle.