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'13 Xc 300 Front/Rear Sprocket opinions please ? i'm at 13/48

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The bike had 13/50 stock as a 250 . I threw a 300 kit on it, had some head work also, it has quite a bit more torque and power everywhere.

I have the Sx Cdi and Red spring with one thread showing. I came off a Yz250 so it's a still a little less aggressive

than a Yz250 or Sx250 but it's pretty close . I ride a gear up to prevent wheel spin when i need to.

 

Anyway, when i added the 300 kit i could immediately tell i needed to remove the 50T rear , I threw on a 49 and was

much happier. Over the winter a buddy noticed my PV was screwed in pretty far and suggested i turn it out. I went from

about 3 threads showing to 1 thread showing--->quite a bit more bottom, immediately i was able to ride more situations

and stay in 3rd without having to downshift to 2nd.

...with all the extra torque i knew right away it could pull a 48T on the rear. I did that and was very happy again.

The bike had much longer legs in both 2nd and 3rd and had a much longer pull overall so that's where im at , 13/48  

 

Here's where i get into a grey area . The bike just has gobs of torque and still has a very healthy 2 stroke mid to top pull.

I am pretty sure i can go one less rear tooth again but instead, i have been thinking about the benefits of a 14T front (countershaft)

as it affects not only wear but also removes some of the negative effect on upsetting suspension (chain slap/tension) .

 

I know that just going to a 14T front with my 48T rear will be too much so i'm thinking either 14/51 (1.5%) for just slightly

taller gearing and "longer legs"    .....or 14/50(3.5%) which i think would be quite more noticeable. Can anyone chime in on this ?

Will I even notice 1.5% taller gearing if I go with a 14/51 ?  Maybe i'm just all off on this...idk.

...And I just bought a new x-ring chain too ...owell   Thanks in advance for any responses !

 

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The bike had 13/50 stock as a 250 . I threw a 300 kit on it, had some head work also, it has quite a bit more torque and power everywhere.

I have the Sx Cdi and Red spring with one thread showing. I came off a Yz250 so it's a still a little less aggressive

than a Yz250 or Sx250 but it's pretty close . I ride a gear up to prevent wheel spin when i need to.

 

Anyway, when i added the 300 kit i could immediately tell i needed to remove the 50T rear , I threw on a 49 and was

much happier. Over the winter a buddy noticed my PV was screwed in pretty far and suggested i turn it out. I went from

about 3 threads showing to 1 thread showing--->quite a bit more bottom, immediately i was able to ride more situations

and stay in 3rd without having to downshift to 2nd.

...with all the extra torque i knew right away it could pull a 48T on the rear. I did that and was very happy again.

The bike had much longer legs in both 2nd and 3rd and had a much longer pull overall so that's where im at , 13/48  

 

Here's where i get into a grey area . The bike just has gobs of torque and still has a very healthy 2 stroke mid to top pull.

I am pretty sure i can go one less rear tooth again but instead, i have been thinking about the benefits of a 14T front (countershaft)

as it affects not only wear but also removes some of the negative effect on upsetting suspension (chain slap/tension) .

 

I know that just going to a 14T front with my 48T rear will be too much so i'm thinking either 14/51 (1.5%) for just slightly

taller gearing and "longer legs"    .....or 14/50(3.5%) which i think would be quite more noticeable. Can anyone chime in on this ?

Will I even notice 1.5% taller gearing if I go with a 14/51 ?  Maybe i'm just all off on this...idk.

...And I just bought a new x-ring chain too ...owell   Thanks in advance for any responses !

 

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I've found 14/50 to be a real nice combination with my 300sx . 14/51 was just a bit too much and the bike accelerates faster with14/50 . With this gearing , the engine stays in each gear just a bit longer and that is a good thing because  of the added torque of the 300sx . It's  able to stay in the sweet spot just a bit longer and it just works better . Now , keep in mind , my bike is used exclusively for cross country running . MX might be very different. A 13T front sprocket is not even an option IMO .

The 300sx has a lot more torque so let that added power do it's job . I should also add that my bike is a 250sx with the 300sx top end , so my 5 speed may be very different than your 6 speed .

Edited by MIMB

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I think the Xc has longer gears . Not sure .  I'm running 13/48 now and it works good, I just think It could pull a little longer gearing like 14/50 .

I ride single track , east coast hare scrambles which open up maybe 1/3 of the race, sometimes up to half the race is wide open fields, fire roads or grass track .

There's sometimes a small amount of Mx sections , more often than not, no Mx involved. And in the woods/single track im mostly on 3rd or 2nd with 13/48

Edited by avocasingletrack

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I'm running 13/48 on my 300XC and really like it but I'm curious how 14/50 would work. Let me know if you pull the trigger.

I run 14/52 on my 450 and its the best of all worlds for that particular bike. Has plenty of grunt but will up and fly with the wide ratio 6 speed.

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I'm running 13/48 on my 300XC and really like it but I'm curious how 14/50 would work. Let me know if you pull the trigger.

I run 14/52 on my 450 and its the best of all worlds for that particular bike. Has plenty of grunt but will up and fly with the wide ratio 6 speed.

I think im gonna try 14/51 which I think would be like 13 / 47.5 if that makes sense ... 

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14 / 50 made the bike put power to the ground  and drive it forward rather than just ripping up the rear tire or wheelies at every corner. No trouble pulling a gear high if needed with a tall 120 MT16 or a trials tire. I had a 52 on the wheel with the trials tire, but it works fine with a 50. 

 

I tried the SX CDI, red pv spring with a shorty silencer. I was faster at the end of most rock enduros with a milder tune.   

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With 14/50 gearing , a 120/90/19 tire , SX cdi , R304 silencer ,PC Plat 2 pipe , red spring , the power is too much for the trail . It will spin the tire hard through the first 3 gears by just rolling the throttle . Impressive in one sense , but not fast .  It has to be detuned a bit for the most effective use of the available power .

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Y'know my go-to gearing has always been 1 up - front,  plus 1 down - rear.  Makes for better useable power.  However the gearbox in this bike still has me undecided right now.  That 6th speed is the icing on the cake, you keep the goat-trail gear, have the top speed, &  keep the hard pulling motor.  A bit more shifting but enjoying it stock for now.

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14 / 50 made the bike put power to the ground  and drive it forward rather than just ripping up the rear tire or wheelies at every corner. No trouble pulling a gear high if needed with a tall 120 MT16 or a trials tire. I had a 52 on the wheel with the trials tire, but it works fine with a 50. 

 

I tried the SX CDI, red pv spring with a shorty silencer. I was faster at the end of most rock enduros with a milder tune.   

you probably get alot of mileage out of 2nd gear with 14/50 ! What class were you running in the enduro's ? Ecea, right ?  It's funny how alot of people think the Xc is sooo aggressive with an Sx box and red spring because in reality it's still not as aggressive as a stock Yz250 or Sx250 , both of which had top AA guys winning on them in the Ecea, Neoc and Wnyoa Hs and Enduro's .

And the guy that's been 1st overall for many recent seasons in Wnyoa ,"Batman" Ben Bouwens won countless overalls on a Yz250 which is more aggressive than an Xc with Sx cdi & red spring . if you've done any Wnyoa you know they are usually alot of super slick roots, rocks, mud and slick muddy grasstrack...worse than the Ecea Oxbo irish valley a few weeks ago .

If i'm in rocks or slick trail i ride a gear taller and lug... i do the same when i ride snow with the studs and i dont have any prob with wheel spin unless i'm in 2nd when i should be in 3rd . i also have the Map switch on the bars but i find the mellow map just causes me probs. I don't doubt you are faster without the sx/red spring. Everyone is different, that's whats nice with the Xc, you can easily make it however you with a few simple things. I think i'm gonna try 14/51 in steel and see how it goes. Thanks for the input on 14/50 mimb and motorhead !

Edited by avocasingletrack

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Avocasingletrack,

You happen to know 300xc with 300sx head and sx cdi unit is same than 250sx upgraded to 300sx. Only the slide is different on carb. Jugs are exactly the same with sx and xc's. So where all that extra viokence comesfrom with 250sx??

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you probably get alot of mileage out of 2nd gear with 14/50 ! What class were you running in the enduro's ? Ecea, right ?  It's funny how alot of people think the Xc is sooo aggressive with an Sx box and red spring because in reality it's still not as aggressive as a stock Yz250 or Sx250 , both of which had top AA guys winning on them in the Ecea, Neoc and Wnyoa Hs and Enduro's .

And the guy that's been 1st overall for many recent seasons in Wnyoa ,"Batman" Ben Bouwens won countless overalls on a Yz250 which is more aggressive than an Xc with Sx cdi & red spring . if you've done any Wnyoa you know they are usually alot of super slick roots, rocks, mud and slick muddy grasstrack...worse than the Ecea Oxbo irish valley a few weeks ago .

If i'm in rocks or slick trail i ride a gear taller and lug... i do the same when i ride snow with the studs and i dont have any prob with wheel spin unless i'm in 2nd when i should be in 3rd . i also have the Map switch on the bars but i find the mellow map just causes me probs. I don't doubt you are faster without the sx/red spring. Everyone is different, that's whats nice with the Xc, you can easily make it however you with a few simple things. I think i'm gonna try 14/51 in steel and see how it goes. Thanks for the input on 14/50 mimb and motorhead !

I advanced myself to A Open / A SR class for 2014 in ECEA and NEOC. The "door to hell" stick forests at the greenbrier enduro on April 13 were 2nd and 3rd gear (18mph posted speed average, but still unachieveable for all but some of the the AA and fastest A riders). It was much tighter than the HS in march. There is no doubt in my mind that some AA racers will increase the hit on a SX or YZ in woods for better results, but there are also a few AAs that will detune an XC(W) to the point of nearly deactivating the PV and still consistently place in the top 10 overall. On helmet cam videos they appear and sound like fast C or slower B riders until you look at their results. The 2011 and 2013 ECEA overall grand champion ran a YZ250 for years with a softened suspension and an aggressive motor tune, and his new ride is essentially a 250SX with XC decals on it (sponsor issue). Jesse Groemm chose a 250SX for NEPG and GNCCs this season and it obviously works for him.

 

Batman is legendary, getting the holeshot over all of the factory GNCC riders at Unadilla while wearing enduro gear on a stock looking bike lets the rest of us know that rider skill is still more important than trick parts. To each their own; I just seem to lack the ability or bravado to confidently control a crisp jetted 300 in tighter trails when it is on the pipe. Watching AA helmet cam videos from 250 riders riding conservatively tells me that there are more than a few effective combinations depending on rider preference.

 

It looked like you were cleaning house at OXBO until the last lap - gas issues or did the weather conditions catch up with you? 

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I advanced myself to A Open / A SR class for 2014 in ECEA and NEOC. The "door to hell" stick forests at the greenbrier enduro on April 13 were 2nd and 3rd gear (18mph posted speed average, but still unachieveable for all but some of the the AA and fastest A riders). It was much tighter than the HS in march.

On helmet cam videos they appear and sound like fast C or slower B riders until you look at their results.

It looked like you were cleaning house at OXBO until the last lap - gas issues or did the weather conditions catch up with you?

Congrats on advancement to A sen. i just self advanced mid season last year. And yeah you are 100% right. Some guys I ride with are polar opposites in preference but they are all A or AA and ride different. I know what u mean, I have some vids where the engine is just lugging, sounds n looks slow. As for the Oxbo I should have won the "idiot of the day" award ! Although every part of me, face and eyes included was covered in mud, I felt good the whole race, i came thru the last lap with snow blowing in my eyes, I saw the flag waving. WOO HOOO 1st (i thought) as I rode back put bike on trailer. I walked up to scoring and realized it was the White Flag. I pulled off with a 9 min lead on 2nd !!!! ....I just had to laugh or else I woulda cried. My 2nd lap time was off, the course guys flagged me right down into a death mud hole as they were trying to re-route, hence my 2nd lap time difference from the other laps.  Hit me up if u wana ride some NePA trail !     

--------------------------------------------------------------------------------------------------

   ---here's a pic of Batman Ben Bouwens passing me

-----------------------------------------------

BatmanBouwens_zpsaffbcaf5.jpg

Edited by avocasingletrack

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I would run a 14/50 before a 13/48 for the benefits that your chain will get. Bigger sprockets make more power because the chain doesn't bend as much . If I was a competitive racer and wanted my bike to do 100 mph a 13/42 should do however I would run a 14/45 for first choice just because the chain bends less .

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I walked up to scoring and realized it was the White Flag. I pulled off with a 9 min lead on 2nd !!!! ....I just had to laugh or else I woulda cried. My 2nd lap time was off, the course guys flagged me right down into a death mud hole as they were trying to re-route, hence my 2nd lap time difference from the other laps.  Hit me up if u wana ride some NePA trail !     

Thanks for the offer, the same invitation applies for the pine barrens. If you want to get some sandy singletrack or whoop practice in prior to sahara sands let me know. Judging by your HS times and your practice terrain, you should do extremely well in rock enduros. Great cross training for HS (not like short NEPG sprints). RORR (reading anthracite - St Clair area)  is coming up in 3 weeks. I am an excellent timekeeper, but at best a fast B / slower A racer in rocks. If none of your group are enduro guys, LMK if you want to sign up on the same minute at RORR or another non-conflict day. Most PA & NY NEOC events fall on enduro days, so I get to Millville area only 3-4 times per year for NEOC.

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