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OK thus might be a loaded question.  I recently purchased a 2006 CRF230F.  Plans are trails and some light road use (installed sicass light kit and plated it).  I have jetted, pro circuit exhaust, front and rear suspension.  What will my best front and rear sprocket combo be?  I took it out today and trails it was great once I hit the road nothing. I know you give up one for the other in thus situation.  Just want some guidance on a happy medium.  Currently stock is what I'm running and could use a replacement..

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For street use you will need much taller gearing.  Add one to the front and be prepared to remove many more from the rear.  With stock gearing Mike Coe said the CRF230 was showing 72 MPH at the rev limiter so at 55 MPH you would be at about 7,500 RPM.

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Damn that is almost exactly what I was getting.  Stock gearing running around 55 and the viper was hovering around that rpm.

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Let's say you want 7,000 RPM at 55 MPH...

(7,000 RPM / 7,500 RPM) x 50 teeth = 0.933 x 50 teeth = 46.667 teeth or 47 teeth at the rear.

Let's say you want 6,500 RPM at 55 MPH...

(6,500 RPM / 7,500 RPM) x 50 teeth = 0.867x 50 teeth = 43.333 teeth or 43 teeth at the rear.

The problem is a stock 230 engine will have trouble pulling big ratios so it isn't always that easy.

BajaTrailRider can help a lot with this as he runs some long/tall ratios...

Edited by VortecCPI

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Let's say you want 7,000 RPM at 55 MPH...

(7,000 RPM / 7,500 RPM) x 50 teeth = 0.933 x 50 teeth = 46.667 teeth or 47 teeth at the rear.

Let's say you want 6,500 RPM at 55 MPH...

(6,500 RPM / 7,500 RPM) x 50 teeth = 0.867x 50 teeth = 43.333 teeth or 43 teeth at the rear.

The problem is a stock 230 engine will have trouble pulling big ratios so it isn't always that easy.

BajaTrailRider can help a lot with this as he runs some long/tall ratios...

 

Do not forget: 15 tooth countershaft sprocket(s) are readily available from "JT" for an XR 250r (same fitment as 150f~230f) you may have to ask your dealer to talk to the "JT" dealer Rep to special order you one but they are available.

(I order 5 at a time as they do wear out)

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I will have to figure out what's going to work the best for me. Not sure what percentages I will be doing either.  What Temps are average for this machine?  Not used to having a Guage  (vapor) that I can monitor all this.

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The best way for me is only  change front sprocket when needed. I think stock gearing is 13/52 ?  I have one stock motor 230 and my stroker 254cc. I would just try like ADN said 14 or 15 on front.We leave off side cover over counter shaft sprocket for easy switch. On the 230 stock motor with 150 wheels we use 15/45 gear,If we truck bike up to forest. I will put the 13 on front as nowhere up there to go over 40mph on trail. On my stroker 15/48 it has done the most hard trail and hill climb.Next new sprockets will be for long distance rides 15/45. For hard single track 13 or 14/ 45. Mine with tall trials tire 15/48 was reported by two KTM riders over 82mph on dirt road, after I let off throttle.

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I put together an excel tool for 230F gearing.  It's handy for benchracing different gearing combos to see where proposed gearing would put your speed and rpms.  Message me your email address and I'll send it your way.

One of these days, I'll follow Red Mesa's method and just put it on google docs...

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8 hours ago, bajatrailrider said:

The best way for me is only  change front sprocket when needed. I think stock gearing is 13/52 ?  I have one stock motor 230 and my stroker 254cc. I would just try like ADN said 14 or 15 on front.We leave off side cover over counter shaft sprocket for easy switch. On the 230 stock motor with 150 wheels we use 15/45 gear,If we truck bike up to forest. I will put the 13 on front as nowhere up there to go over 40mph on trail. On my stroker 15/48 it has done the most hard trail and hill climb.Next new sprockets will be for long distance rides 15/45. For hard single track 13 or 14/ 45. Mine with tall trials tire 15/48 was reported by two KTM riders over 82mph on dirt road, after I let off throttle.

Back in the old days when we had the two 1984 Al Baker XR265Rs we each had three counter sprockets and used to leave with one and carry the other two with us.  If the track was short we used a 13-tooth.  If the track was long we used a 15-tooth.  We used a 14-tooth for most work but the 13 and 15 were used more often than you might think.  Those crazy Al Baker engines could pull the 15 with no trouble and you could attain speeds that were scary for the small chassis.  The 13 was useful for slow short tight work because the engines were pretty weak at the bottom with the huge Mugen "Desert Grind" cams.

One of the reasons I LOVE my CRF230 is that the chassis is very close to that of the old 84/85 XR250, which went on to become the new XR200 chassis.  My 230 was a natural fit for me after so many years on the small Al Baker XR265R chassis.  The late-model XR250 felt big and tall and HUGE compared to the old Al Baker bike and the CRF230.  Great for slow short tight work and scary for fast long open work...

Edited by VortecCPI

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I forgot to leave out some gearing info why we,like to gear up the 230s. This may not apply to riding in the States. We gear up our 230s (and other bikes) because there is always dirt road after trail. Like anybody we want gearing for hard slow trail and dirt road.We dont gear up to ride fast.We gear up  on dirt roads. To run at the least RPMs at 55/60mph less fuel (as Fuel hard to get on long runs) less oil consumption,less ware and tear on piston/valve train. At 55 MPH on dirt road for few hours 13/52 stock gearing,way too many wasted RPMs. So we learn to ride hard single track with Hi gearing. Worst case put 13t on trail.Big help grinding swing arm out to get all chain adjustment.

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I forgot to leave out some gearing info why we,like to gear up the 230s. This may not apply to riding in the States. We gear up our 230s (and other bikes) because there is always dirt road after trail. Like anybody we want gearing for hard slow trail and dirt road.We dont gear up to ride fast.We gear up  on dirt roads. To run at the least RPMs at 55/60mph less fuel (as Fuel hard to get on long runs) less oil consumption,less ware and tear on piston/valve train. At 55 MPH on dirt road for few hours 13/52 stock gearing,way too many wasted RPMs. So we learn to ride hard single track with Hi gearing. Worst case put 13t on trail.Big help grinding swing arm out to get all chain adjustment.


+1 a few different reasons for me but all above points are good.
For my stuff:
Mostly Fuel mileage and my engines don't ever see over 8K rpm, as well as 1st gear is almost useless it's so low anyway.
I have ground on my swing arms as much as possible for maximum axle movement.
various reasons like tire selection and traction scenarios, keep the front wheel light, front wheel traction, etc. (A long time ago, I rode short track for several years)
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On 4/9/2017 at 1:45 PM, Jpxj2 said:

 

OK thus might be a loaded question.

 

There is this thread form some years ago that had conversation about swapping gears from L/M to F models, I never deciphered if these could be interchanged without changing out the whole gear set. Could the individual gears could be swapped to better accommodate one's use of the 230?

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1 hour ago, NEODS said:

There is this thread form some years ago that had conversation about swapping gears from L/M to F models, I never deciphered if these could be interchanged without changing out the whole gear set. Could the individual gears could be swapped to better accommodate one's use of the 230?

Love this question if the L model has Higher 6th gear then F  That would work for me.

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On April 10, 2017 at 8:19 AM, bajatrailrider said:

I forgot to leave out some gearing info why we,like to gear up the 230s. This may not apply to riding in the States. We gear up our 230s (and other bikes) because there is always dirt road after trail. Like anybody we want gearing for hard slow trail and dirt road.We dont gear up to ride fast.We gear up  on dirt roads. To run at the least RPMs at 55/60mph less fuel (as Fuel hard to get on long runs) less oil consumption,less ware and tear on piston/valve train. At 55 MPH on dirt road for few hours 13/52 stock gearing,way too many wasted RPMs. So we learn to ride hard single track with Hi gearing. Worst case put 13t on trail.Big help grinding swing arm out to get all chain adjustment.

I, also, ground out the swing arm to gain full adjustment from the snail adjusters for switching from 12-15 teeth while riding.

Even if the 230 struggles to pull 15/45 in sixth gear, it's nice to have on those long downhills on the highway to rest the motor and save fuel with the throttle barely cracked open.  You can always downshift if you need more power.

 

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I have tried a few combinations on my street legal 230 and have ended up with a 14 counter and 45 rear this equates to a 321 ratio final drive and still has plenty of pull down low and I can run 50-55 mph all day long and not worry about it.  Top speed is about 72-75mph.  My bike has been modded with a 89a web cam, 67mm big bore with Wossner forged piston and the intake has been ported.  Power up kit with a Uni filter as well has been done to the bike.  I absolutely love trail hoppin and not worrying about a ticket on the street.  

IMG_0384.JPG

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1 hour ago, Titanman said:
1 hour ago, Titanman said:

I will add my modded 230 will NOT pull a rear sprocket any smaller than a 45 very well top end.  

Your 14/45 very close to my 15/48 Dont know what tire you run,but the 400x18 MT43 I use very tall. Mine with 6mm stroke pulls 6th way too easy. Cant wait for my new gear change 15/45 for long easy rides. 14/45 most of the time for hard trail will put me back to 15/48.

 

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Has anyone done the 6mm stroke with stock or near stock bore?  I wonder if I could get away with that since my motor has so few miles, without boring.

 

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4 minutes ago, Baja Rambler said:

Has anyone done the 6mm stroke with stock or near stock bore?  I wonder if I could get away with that since my motor has so few miles, without boring.

 

Yes Baja Hooter you could do it BUT. Example back in the stone age before you where riding. My TT50 bore and stroke to 650cc,ported head big intake valve,cam/big carb/pipe. The Monkeys TT650 done at same time but only Bore ,stroke, stock cam,head  . Mine pulled his over 10 bike lengths,his had some torque but boring to ride. He soon pulled motor re did like mine.

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