Roczen - Factory Transmission

cwtoyota wrote:

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.There have been weaknesses in the production transmissions in some...

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.

There have been weaknesses in the production transmissions in some models over the years.   Those may not be weakness in terms of durability or torque holding capacity, but also in terms of shift quality.  They will use a different shift detent cam or a modified production cam to reduce the chance of the bike going into neutral on a light shift by the rider or a bump to the shift lever.  They can also increase the tension of the shift detent spring to more tightly hold the bike in each gear position.   Anyone with some basic technical understanding and fabricating skill can do those mods to a bike, especially the experienced guys on support / satellite teams.

I have not ridden any RMZ model in years, so I don't really know if they shift poorly or have durability issues.

There were some KX250F models in the past with a false neutral between 2nd & 3rd gear for example.  An upgrade shift cam and detent cam would likely make those bikes 100% reliable.

The YZ250 two strokes that a lot of us ride have a transmission made of glass.  Gears are weak, shift forks are a bad design, etc.  I do a host of mods to them and replace nearly everything inside to make them safe.

It is my understanding that (at least in the past) they could not reduce the number of gears in the transmission per AMA rules.  They just put a plastic gear in there to take up that space while also reducing weight.   Obviously the plastic gear would be wiped out if the rider engaged it, so those transmissions have a different shift cam that eliminates the corresponding shift position, turning them into a four speed.

It is also my understanding that some teams have different primary gears available to them.  The primary drive gear is on the end of the crankshaft and the primary driven gear is the huge gear on the back of the clutch basket.  Swapping these gears around changes the ratio of all four or five gears in the transmission, it is equivalent to changing the sprockets without the effects on chassis dynamics due to chain torque.

When you hear a factory rider say they're "clearing the triple in 1st gear", they likely have something similar to our 2nd gear due to the changes inside the gearbox and primary drive ratio changes.   Also the change in ratio between each gear may be different.

cwtoyota wrote:

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.There have been weaknesses in the production transmissions in some...

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.

There have been weaknesses in the production transmissions in some models over the years.   Those may not be weakness in terms of durability or torque holding capacity, but also in terms of shift quality.  They will use a different shift detent cam or a modified production cam to reduce the chance of the bike going into neutral on a light shift by the rider or a bump to the shift lever.  They can also increase the tension of the shift detent spring to more tightly hold the bike in each gear position.   Anyone with some basic technical understanding and fabricating skill can do those mods to a bike, especially the experienced guys on support / satellite teams.

I have not ridden any RMZ model in years, so I don't really know if they shift poorly or have durability issues.

There were some KX250F models in the past with a false neutral between 2nd & 3rd gear for example.  An upgrade shift cam and detent cam would likely make those bikes 100% reliable.

The YZ250 two strokes that a lot of us ride have a transmission made of glass.  Gears are weak, shift forks are a bad design, etc.  I do a host of mods to them and replace nearly everything inside to make them safe.

It is my understanding that (at least in the past) they could not reduce the number of gears in the transmission per AMA rules.  They just put a plastic gear in there to take up that space while also reducing weight.   Obviously the plastic gear would be wiped out if the rider engaged it, so those transmissions have a different shift cam that eliminates the corresponding shift position, turning them into a four speed.

It is also my understanding that some teams have different primary gears available to them.  The primary drive gear is on the end of the crankshaft and the primary driven gear is the huge gear on the back of the clutch basket.  Swapping these gears around changes the ratio of all four or five gears in the transmission, it is equivalent to changing the sprockets without the effects on chassis dynamics due to chain torque.

When you hear a factory rider say they're "clearing the triple in 1st gear", they likely have something similar to our 2nd gear due to the changes inside the gearbox and primary drive ratio changes.   Also the change in ratio between each gear may be different.

Meister wrote:

Regarding your last paragraph... Id venture to say the new gen yam could get over a 70-75' triple in 1st bone stock.. Burkeen hit loraccos leap...

Regarding your last paragraph... Id venture to say the new gen yam could get over a 70-75' triple in 1st bone stock.. Burkeen hit loraccos leap in 2nd with just an ecu as far as mods. Plessinger said he did too but everyone pulled the "factory bike" card. Burkeen debunked that theory tho. Maybe factory ktms use the longer 2nd outdoors too but i would have guessed a more useable 3rd.. 

I always figured factory transmission had a super useable second. Firm shifting but very positive feeling. I'm guessing most of a SX in 2nd unless toward the end of a high speed rythem or the start. I duno about now with 9 whoops, but i do know theyd use 4th or 5th in whoops on long sets. Plenty of videos of guys upshifting 2-3 times in the air before the corner. I still feel like, based on motor sound alone, that the fast 250f guys are in a super high gear going in too.. Their top teir 250s are beasts and can handle it. If i could afford to have and maintain a star yamaha, id probably ditch my stock 450.. I cant imagine what it's actually like.. Id love one somewhere like Daytona lol.. 

Teej317 wrote:

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all...

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all the way over from essentially a stand still. Had to be 1st gear. 

Teej317 wrote:

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all...

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all the way over from essentially a stand still. Had to be 1st gear. 

SoCalMX70 wrote:

Was wondering if anyone else caught that line. Only guy doing it.

mxav8r wrote:

Factory transmission and shift drum from another brand and a couple generations old.

Factory transmission and shift drum from another brand and a couple generations old.

Teej317 wrote:

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all...

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all the way over from essentially a stand still. Had to be 1st gear. 

SoCalMX70 wrote:

Was wondering if anyone else caught that line. Only guy doing it.

Meister wrote:

It was sick, but my brains telling me someone else was doing it too.. could be brain farting tho.. sent to the moon to drop out...

It was sick, but my brains telling me someone else was doing it too.. could be brain farting tho.. sent to the moon to drop out of the sky lol.. 

 

Edit, was it savatgy?

Teej317 wrote:

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all...

That tight rutted left hander that dipped down then straight up a jump face was pretty cool. Roczen was the only one I saw triple all the way over from essentially a stand still. Had to be 1st gear. 

SoCalMX70 wrote:

Was wondering if anyone else caught that line. Only guy doing it.

Meister wrote:

It was sick, but my brains telling me someone else was doing it too.. could be brain farting tho.. sent to the moon to drop out...

It was sick, but my brains telling me someone else was doing it too.. could be brain farting tho.. sent to the moon to drop out of the sky lol.. 

 

Edit, was it savatgy?

Teejay wrote:

Slightly off the original topic but was Kenny running the electric start at A1?  couldn't see on the broadcast but I was thinking about Chase's stall...

Slightly off the original topic but was Kenny running the electric start at A1?  couldn't see on the broadcast but I was thinking about Chase's stall and wondering how costly that could have been for Roczen.

soggy wrote:

that shift drum 🤑

soggy wrote:

that shift drum 🤑

mxav8r wrote:

Works primary gear and balance shaft

Works primary gear and balance shaft

soggy wrote:

that shift drum 🤑

mxav8r wrote:

Works primary gear and balance shaft

Works primary gear and balance shaft

cwtoyota wrote:

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.There have been weaknesses in the production transmissions in some...

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.

There have been weaknesses in the production transmissions in some models over the years.   Those may not be weakness in terms of durability or torque holding capacity, but also in terms of shift quality.  They will use a different shift detent cam or a modified production cam to reduce the chance of the bike going into neutral on a light shift by the rider or a bump to the shift lever.  They can also increase the tension of the shift detent spring to more tightly hold the bike in each gear position.   Anyone with some basic technical understanding and fabricating skill can do those mods to a bike, especially the experienced guys on support / satellite teams.

I have not ridden any RMZ model in years, so I don't really know if they shift poorly or have durability issues.

There were some KX250F models in the past with a false neutral between 2nd & 3rd gear for example.  An upgrade shift cam and detent cam would likely make those bikes 100% reliable.

The YZ250 two strokes that a lot of us ride have a transmission made of glass.  Gears are weak, shift forks are a bad design, etc.  I do a host of mods to them and replace nearly everything inside to make them safe.

It is my understanding that (at least in the past) they could not reduce the number of gears in the transmission per AMA rules.  They just put a plastic gear in there to take up that space while also reducing weight.   Obviously the plastic gear would be wiped out if the rider engaged it, so those transmissions have a different shift cam that eliminates the corresponding shift position, turning them into a four speed.

It is also my understanding that some teams have different primary gears available to them.  The primary drive gear is on the end of the crankshaft and the primary driven gear is the huge gear on the back of the clutch basket.  Swapping these gears around changes the ratio of all four or five gears in the transmission, it is equivalent to changing the sprockets without the effects on chassis dynamics due to chain torque.

When you hear a factory rider say they're "clearing the triple in 1st gear", they likely have something similar to our 2nd gear due to the changes inside the gearbox and primary drive ratio changes.   Also the change in ratio between each gear may be different.

cwtoyota wrote:

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.There have been weaknesses in the production transmissions in some...

The term "factory transmission" from the rider's perspective could mean something from a 3rd party supplier too.

There have been weaknesses in the production transmissions in some models over the years.   Those may not be weakness in terms of durability or torque holding capacity, but also in terms of shift quality.  They will use a different shift detent cam or a modified production cam to reduce the chance of the bike going into neutral on a light shift by the rider or a bump to the shift lever.  They can also increase the tension of the shift detent spring to more tightly hold the bike in each gear position.   Anyone with some basic technical understanding and fabricating skill can do those mods to a bike, especially the experienced guys on support / satellite teams.

I have not ridden any RMZ model in years, so I don't really know if they shift poorly or have durability issues.

There were some KX250F models in the past with a false neutral between 2nd & 3rd gear for example.  An upgrade shift cam and detent cam would likely make those bikes 100% reliable.

The YZ250 two strokes that a lot of us ride have a transmission made of glass.  Gears are weak, shift forks are a bad design, etc.  I do a host of mods to them and replace nearly everything inside to make them safe.

It is my understanding that (at least in the past) they could not reduce the number of gears in the transmission per AMA rules.  They just put a plastic gear in there to take up that space while also reducing weight.   Obviously the plastic gear would be wiped out if the rider engaged it, so those transmissions have a different shift cam that eliminates the corresponding shift position, turning them into a four speed.

It is also my understanding that some teams have different primary gears available to them.  The primary drive gear is on the end of the crankshaft and the primary driven gear is the huge gear on the back of the clutch basket.  Swapping these gears around changes the ratio of all four or five gears in the transmission, it is equivalent to changing the sprockets without the effects on chassis dynamics due to chain torque.

When you hear a factory rider say they're "clearing the triple in 1st gear", they likely have something similar to our 2nd gear due to the changes inside the gearbox and primary drive ratio changes.   Also the change in ratio between each gear may be different.

38special wrote:

I'd love to see your YZ250 mods, if you're willing to share.  Maybe start a new thread in the Tech section?