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Thinking the Unthinkable - Auto Clutch on a Competition Trials Bike

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Motobene - I hesitate to ask, but have you found a need to use Rekluse oil with their auto clutches? The specs don't indicate that it's anything special, and I'd rather stick with Honda oil for better availability.

 
I talked one of their engineers, engineer-to-engineer, about Rekluse and tribology related to various clutch behaviors I had experienced on a more difficult Rekluse implementation. Out of that conversation
came the admission that "Shell Rotella T4 is a near equivalent to our branded oil", which could be a touch better than what I have long used, but I've had no reason to find out.

Shell Rotella is a diesel (more stressed) engine oil that also happens to have the additives conforming to JASO MA2, which is: for modern 4 stroke (gasoline) motorcycle engines that shares engine oil with a wet friction clutch.
There are three Rotellas, varying in base stock. T4 is all mineral or petroleum base stock, T6 all synthetic, and T5 in between maybe half and half. The more the synthetic base stock thew higher the price.
Being a diesel oil gets a really robust anti-wear additive package and longer range. Not that I put long miles between motorcycle oil changes, but I had the stuff around anyway and long used it in all my 4-stroke motos
and ranch ATV.

Those SAE numbers we all know so well - but don't - aren't units of viscosity, but rather represent a range of viscosities reflecting actual viscosity with respect to temperature indirectly. The broader range of the T6 synthetic's
5Winter40 versus the T4's 15Winter40 very indirectly highlights the a higher VI or viscosity index of the synthetic base stock, as in changes in viscosity less over the full operating temperature. Strange, yes? But that's the
bizarre SAE system for describing oil.

I went early on with a diesel oil in my 4-stroke bikes because it is a diesel oil and I have a diesel truck and diesel equipment already. That Rotella also is JASO MA2 was icing on the cake. I started at the T5, then I found
T6 to be slightly better in the KLR 685 with Rekluse clutch, as it reduced judder when cold. Not very scientific, but that's my story. I can tell you that T6 is about as good as you can get if you have a Rekluse. I don't
back off from this thicker diesel oil even in the cold season, as the bike will warm the oil. I've had the clutch on the Beta not release when the bike got cold soaked being pulled on a trailer in 20-degree air.
At the trailhead, I started the bike and let it idle for a minute, then rolled down hill and snicked it into 2nd gear and rode it around until the engine warmed the oil enough to let the clutch release at idle.
within an hour into the ride, the New Mexico sun had raised the ambient temp by 20 degrees to perfect!

The diesel oils may not be practical for Siberia in winter, but how many of us ride in Siberia in the winter?
 
I talked one of their engineers, engineer-to-engineer, about Rekluse and tribology related to various clutch behaviors I had experienced on a more difficult Rekluse implementation. Out of that conversation
came the admission that "Shell Rotella T4 is a near equivalent to our branded oil", which could be a touch better than what I have long used, but I've had no reason to find out.

Shell Rotella is a diesel (more stressed) engine oil that also happens to have the additives conforming to JASO MA2, which is: for modern 4 stroke (gasoline) motorcycle engines that shares engine oil with a wet friction clutch.
There are three Rotellas, varying in base stock. T4 is all mineral or petroleum base stock, T6 all synthetic, and T5 in between maybe half and half. The more the synthetic base stock thew higher the price.
Being a diesel oil gets a really robust anti-wear additive package and longer range. Not that I put long miles between motorcycle oil changes, but I had the stuff around anyway and long used it in all my 4-stroke motos
and ranch ATV.

Those SAE numbers we all know so well - but don't - aren't units of viscosity, but rather represent a range of viscosities reflecting actual viscosity with respect to temperature indirectly. The broader range of the T6 synthetic's
5Winter40 versus the T4's 15Winter40 very indirectly highlights the a higher VI or viscosity index of the synthetic base stock, as in changes in viscosity less over the full operating temperature. Strange, yes? But that's the
bizarre SAE system for describing oil.

I went early on with a diesel oil in my 4-stroke bikes because it is a diesel oil and I have a diesel truck and diesel equipment already. That Rotella also is JASO MA2 was icing on the cake. I started at the T5, then I found
T6 to be slightly better in the KLR 685 with Rekluse clutch, as it reduced judder when cold. Not very scientific, but that's my story. I can tell you that T6 is about as good as you can get if you have a Rekluse. I don't
back off from this thicker diesel oil even in the cold season, as the bike will warm the oil. I've had the clutch on the Beta not release when the bike got cold soaked being pulled on a trailer in 20-degree air.
At the trailhead, I started the bike and let it idle for a minute, then rolled down hill and snicked it into 2nd gear and rode it around until the engine warmed the oil enough to let the clutch release at idle.
within an hour into the ride, the New Mexico sun had raised the ambient temp by 20 degrees to perfect!

The diesel oils may not be practical for Siberia in winter, but how many of us ride in Siberia in the winter?
Thanks, that's good to know. I'm familiar with BITOG and know that Rotella is a favorite. I'll use up my Honda oil and give T6 a try in the bike. I doubt I'll get my EXP disc cold enough to freeze the wedges in the parked position, but I'll remember what you said about letting the engine warm it up.

Walmart, parts stores, and truck stops usually have T6, so it should be even easier to find than Honda oil. My bike has relatively low OCIs, so being able to pick up a few quarts on the road is another benefit.

My LHRB assembly arrived yesterday, so I need to get on with the installation.
 
I talked one of their engineers, engineer-to-engineer, about Rekluse and tribology related to various clutch behaviors I had experienced on a more difficult Rekluse implementation. Out of that conversation
came the admission that "Shell Rotella T4 is a near equivalent to our branded oil", which could be a touch better than what I have long used, but I've had no reason to find out.

Shell Rotella is a diesel (more stressed) engine oil that also happens to have the additives conforming to JASO MA2, which is: for modern 4 stroke (gasoline) motorcycle engines that shares engine oil with a wet friction clutch.
There are three Rotellas, varying in base stock. T4 is all mineral or petroleum base stock, T6 all synthetic, and T5 in between maybe half and half. The more the synthetic base stock thew higher the price.
Being a diesel oil gets a really robust anti-wear additive package and longer range. Not that I put long miles between motorcycle oil changes, but I had the stuff around anyway and long used it in all my 4-stroke motos
and ranch ATV.

Those SAE numbers we all know so well - but don't - aren't units of viscosity, but rather represent a range of viscosities reflecting actual viscosity with respect to temperature indirectly. The broader range of the T6 synthetic's
5Winter40 versus the T4's 15Winter40 very indirectly highlights the a higher VI or viscosity index of the synthetic base stock, as in changes in viscosity less over the full operating temperature. Strange, yes? But that's the
bizarre SAE system for describing oil.

I went early on with a diesel oil in my 4-stroke bikes because it is a diesel oil and I have a diesel truck and diesel equipment already. That Rotella also is JASO MA2 was icing on the cake. I started at the T5, then I found
T6 to be slightly better in the KLR 685 with Rekluse clutch, as it reduced judder when cold. Not very scientific, but that's my story. I can tell you that T6 is about as good as you can get if you have a Rekluse. I don't
back off from this thicker diesel oil even in the cold season, as the bike will warm the oil. I've had the clutch on the Beta not release when the bike got cold soaked being pulled on a trailer in 20-degree air.
At the trailhead, I started the bike and let it idle for a minute, then rolled down hill and snicked it into 2nd gear and rode it around until the engine warmed the oil enough to let the clutch release at idle.
within an hour into the ride, the New Mexico sun had raised the ambient temp by 20 degrees to perfect!

The diesel oils may not be practical for Siberia in winter, but how many of us ride in Siberia in the winter?
Just from personal experience...

I drag raced Chevy V8's for over a decade. We had street cars in the 1,000-1,500hp range. We were pushing these mirrors harder than expected and never had an oiling issue. Most all of us grew up with Rotella T4 on the farm. It worked, was cheap, was on hand...we used it with zero issues.

Fast forward to 2017 and I buy a brand new Yamaha FZ07. My old engine building days won't let me keep the OEM oil in the bike for 600 miles as suggested, so I ride home and drop the oil. Refill with T4. A few days later I look at the sight glass and it's pure black. WTF? That's gotta come out. I drain the oil and it gushes out like water.

I send it to Blackstone labs for analysis and the get in touch to verify the mileage on the oil. On the form I filled out that the oil had 200 miles on it and they couldn't believe it. Wear metals and such for a new engine weren't crazy, but they said the viscosity was just gone. The oil was beat to death in 200 miles.

I didn't know what to do, but I wasn't putting T4 back in anything. Called the machinist I knew from the drag racing days and he's seen the same thing. "Rotella ain't what it used to be. We're losing cams and lifters on stock rebuilds like I've never seen in 50 years".

I noticed Yamalube was actually cheaper than Rotella, and if the bike dies under warranty while running Yamalube then I should have leg to stand on. Also, not that Yamaha recommended a 6,000 mile oil change interval on this bike.

I swapped to Yamalube conventional oil and started sending in a sample to be analyzed every 1,500 miles and the results were coming back with sparkling results. Blackstone labs aren't bike people, but my results were so drastic that the contacted me again to clarify things. Turns out they don't just turn around oil samples, but they keep a database on each model of vehicle to establish a baseline. So I informed them how Yamaha uses the CP2 engine in multiple models. FZ07, MT07, Tracer 700, Tenere 700...they had no idea but it really expanded the database.


Long story short, I didn't really know what Yamalube is, but I use it in everything now. I kept sending oil samples from that bike all the way up to the first 6,000 recommended oil change interval and Blackstone said the oil is clean and healthy. No signs of degradation. I finally got to 10,000 miles and changed it simply because it felt wrong!

I don't know what changed with Rotella, but I can't trust it anymore. The Rotella Faithful Follower's don't like to hear this, but I'm just going on the data from my oil analysis and my old engine builder having the same experience. Yamalube has proven itself as very good oil, and I'll keep using it until periodic oil analysis reports says it's not doing the job anymore.
 
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Just from personal experience...

I drag raced Chevy V8's for over a decade. We had street cars in the 1,000-1,500hp range. We were pushing these mirrors harder than expected and never had an oiling issue. Most all of us grew up with Rotella T4 on the farm. It worked, was cheap, was on hand...we used it with zero issues.

Fast forward to 2017 and I buy a brand new Yamaha FZ07. My old engine building days won't let me keep the OEM oil in the bike for 600 miles as suggested, so I ride home and drop the oil. Refill with T4. A few days later I look at the sight glass and it's pure black. WTF? That's gotta come out. I drain the oil and it gushes out like water.

I send it to Blackstone labs for analysis and the get in touch to verify the mileage on the oil. On the form I filled out that the oil had 200 miles on it and they couldn't believe it. Wear metals and such for a new engine weren't crazy, but they said the viscosity was just gone. The oil was beat to death in 200 miles.

I didn't know what to do, but I wasn't putting T4 back in anything. Called the machinist I knew from the drag racing days and he's seen the same thing. "Rotella ain't what it used to be. We're losing cams and lifters on stock rebuilds like I've never seen in 50 years".

I noticed Yamalube was actually cheaper than Rotella, and if the bike dies under warranty while running Yamalube then I should have leg to stand on. Also, not that Yamaha recommended a 6,000 mile oil change interval on this bike.

I swapped to Yamalube conventional oil and started sending in a sample to be analyzed every 1,500 miles and the results were coming back with sparkling results. Blackstone labs aren't bike people, but my results were so drastic that the contacted me again to clarify things. Turns out they don't just turn around oil samples, but they keep a database on each model of vehicle to establish a baseline. So I informed them how Yamaha uses the CP2 engine in multiple models. FZ07, MT07, Tracer 700, Tenere 700...they h
Interesting. Thanks for the insight. Oil formulations do change over time, and I don't doubt what you said about T4. I asked MB about his experience with oil because I know how much of a difference it can make in a bike's transmission and I assumed it can impact the performance of an auto clutch, too.

I've had UOAs through Blackstone before. I know they have a database that goes back years, if not to their origins. I haven't consulted BITOG on any of this yet. Someone must've sent in a unused, recent sample of T4 for analysis by now.

I'm so gentle to my CRF450L that keeping the air filter clean should allow for an extended OCI of 1000-1500 miles on most any oil.
 
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Just from personal experience...

I drag raced Chevy V8's for over a decade. We had street cars in the 1,000-1,500hp range. We were pushing these mirrors harder than expected and never had an oiling issue. Most all of us grew up with Rotella T4 on the farm. It worked, was cheap, was on hand...we used it with zero issues.

Fast forward to 2017 and I buy a brand new Yamaha FZ07. My old engine building days won't let me keep the OEM oil in the bike for 600 miles as suggested, so I ride home and drop the oil. Refill with T4. A few days later I look at the sight glass and it's pure black. WTF? That's gotta come out. I drain the oil and it gushes out like water.

I send it to Blackstone labs for analysis and the get in touch to verify the mileage on the oil. On the form I filled out that the oil had 200 miles on it and they couldn't believe it. Wear metals and such for a new engine weren't crazy, but they said the viscosity was just gone. The oil was beat to death in 200 miles.

I didn't know what to do, but I wasn't putting T4 back in anything. Called the machinist I knew from the drag racing days and he's seen the same thing. "Rotella ain't what it used to be. We're losing cams and lifters on stock rebuilds like I've never seen in 50 years".

I noticed Yamalube was actually cheaper than Rotella, and if the bike dies under warranty while running Yamalube then I should have leg to stand on. Also, not that Yamaha recommended a 6,000 mile oil change interval on this bike.

I swapped to Yamalube conventional oil and started sending in a sample to be analyzed every 1,500 miles and the results were coming back with sparkling results. Blackstone labs aren't bike people, but my results were so drastic that the contacted me again to clarify things. Turns out they don't just turn around oil samples, but they keep a database on each model of vehicle to establish a baseline. So I informed them how Yamaha uses the CP2 engine in multiple models. FZ07, MT07, Tracer 700, Tenere 700...they had no idea but it really expanded the database.


Long story short, I didn't really know what Yamalube is, but I use it in everything now. I kept sending oil samples from that bike all the way up to the first 6,000 recommended oil change interval and Blackstone said the oil is clean and healthy. No signs of degradation. I finally got to 10,000 miles and changed it simply because it felt wrong!

I don't know what changed with Rotella, but I can't trust it anymore. The Rotella Faithful Follower's don't like to hear this, but I'm just going on the data from my oil analysis and my old engine builder having the same experience. Yamalube has proven itself as very good oil, and I'll keep using it until periodic oil analysis reports says it's not doing the job anymore.
Yama lube dyno the highest hp and torque numbers in 2005. Followed by Mobil. This info was given by a guru who looked both ways to see if any one else was listening after I asked...Daytona years
 
Yama lube dyno the highest hp and torque numbers in 2005. Followed by Mobil. This info was given by a guru who looked both ways to see if any one else was listening after I asked...Daytona years
That's very interesting. I would love to know what Yamalube is, but I didn't think we're gonna find it cheaper bottles in it's "original" branding at it's about the cheapest I can find. $20/gallon currently
 
That's very interesting. I would love to know what Yamalube is, but I didn't think we're gonna find it cheaper bottles in it's "original" branding at it's about the cheapest I can find. $20/gallon currently
Well this crowd got big on small details..I waited till no one was around and asked did you ever coat a chain and dyno...yes somewhere in my archives is the 30 different baked on coatings for parts...yes the chain worked. So did a cx500 turbo with a pair of vise grips on the waste gate...130hp at the back tire on a superflow dynamometer. Crazy stuff!
 
That's very interesting. I would love to know what Yamalube is, but I didn't think we're gonna find it cheaper bottles in it's "original" branding at it's about the cheapest I can find. $20/gallon currently
 
Interesting. Thanks. I should dig out my old reports and look at the ingredients along with Rotella. That was 2017 and memory don't go back that far.
 
When I was doing loop trail development on my property, I was using my `17 Sherco 250 Factory as transportation. Of course there were a gazillion get of then later get on, with same number of engine stop and starts. At least it's a 250, and the previous version of the carbureted Sherco 250 is one of the easier starting bikes on earth very light sweep-through kick does it... every time. What I found more a pain was trying to find neutral before I rolled to a stop. Not that I HAD to be in neutral, but it would be nice.

Anyway... I kept thinking how nice a capable electric bike would be for this kind of work, or my TRS 250 electric start. Now combine the TRS 250 with an auto clutch and I'd be there! My 250 is also a RR-model-based X-Track model, but all that X-Track stuff - the seat and larger tank and plastic over frame came off when I assembled the bike from the crate and it hasn't been touched since. I should have instead bought a Gold model to get the big Reiger shock. Lesson learned :-(

I still have the option to let EFM have a crack at stacking a ball-ramp mechanism on top of a TRS clutch (see the second post in this thread). I would not need the clutch slave cylinder in the clutch cover then, and I bet a cover spacer would be required to make room for the ball-ramp pack. The jury is still out on ball-ramp-style applied to a 3-fiber-plate, 2-steel-plate 'diaphragm' clutch with much higher net spring clamping force. Could require lots of tungsten carbide balls to get enough 'centripetal' force to attain the required clamping force at a low enough rpm.

Maybe I should finally give Gary a ring? The project cost to me would be buying and sending him a whole new TRS clutch:
Parts to EFM for Auto Clutch Project.jpg

Some design collaboration, and time in testing beta and then prototype. I know it can be done, the question is only how, and how tick a spacer on the clutch cover would be required to give room for a ball-ramp pack.

These-type clutches have steel clutch baskets with tiny tangs too small to thread into. But the backer part of the ball ramp could be machined in steel, adding the rotational inertia to the TRS motor that is so needed to get rid of stalls
(though going auto usually cures the stalling problem 100%). The steel part would have a boss to precisely fit the tangs and we'd use spot tig welding instead of fasteners. Hmm....

I just reached out to Gary at EFM. I'll let you all know what comes of that.
 
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Forgot to post this earlier, apparently, when asked about oil.

I talked one of the Rekluse engineers years ago, engineer-to-engineer, about Rekluse and tribology and clutch behaviors I had experienced on a more difficult Rekluse implementation. Out of that conversation
came the admission that "Shell Rotella T4 is a near equivalent to our branded oil" (wonder who supplies that to them?) Their oil could be a touch better than what I have long used, but I've had no reason to find out, as I went with
Rotella T6 long ago and it has worked marvelously with the Rekluse auto clutches.

Shell Rotella is a diesel (more stressed) engine oil that also happens to have the additives conforming to JASO MA2, which is: for modern 4 stroke (gasoline) motorcycle engines that shares engine oil with a wet friction clutch.
There are three Rotellas, varying in base stock. T4 is all mineral or petroleum base stock, T6 all synthetic, and T5 in between maybe half and half. The more the synthetic base stock thew higher the price.
Being a diesel oil gets a really robust anti-wear additive package and longer range. Not that I put long miles between motorcycle oil changes, but I had the stuff around anyway and long used it in all my 4-stroke motos
and ranch ATV.

Those SAE numbers we all know so well - but don't - aren't units of viscosity, but rather represent a range of viscosities reflecting actual viscosity with respect to temperature indirectly. The broader range of the T6 synthetic's
5Winter40 versus the T4's 15Winter40 very indirectly highlights the a higher VI or viscosity index of the synthetic base stock, as in changes in viscosity less over the full operating temperature. Strange, yes? But that's the
bizarre SAE system for describing oil.

SAE number, code for specifying the viscosity of lubricating oil, established by the U.S. Society of Automotive Engineers a long time ago has the numbers for crankcase lubricants range from 5 to 50, and for for transmission
and axle lubricants they ranging from 75 to 250
; the lower the number, the more readily the oil flows. Other than that, the system is, well, confusing, and why you should not buy suspension oils that don't show actual
viscosity at cold and hot temperatures, for example SUS (Saybolt universal seconds).

The 5W part of the oil isn't thinner in viscosity when it's cold than when it's at 100 degrees C and supposedly a 40. It's actual viscosity is the opposite, as in thinner when hot. Anyway, if an oil does not provide a specific
viscosity at both cold and hot temperatures, you can't know the viscosity other than some rough idea from the SAE numbers. 0W20 is thinner than 15W40, but like so many things, it complicated. And I've measured 7W fork oils
that were thicker at room temperature than 10W fork oils.

I don't back off from this thicker diesel oil even in the cold season, as the bike will warm the oil quickly to where it isn't too thick. I've had the clutch on the Beta not release when the bike got cold soaked being pulled on a trailer in 20-degree air.
At the trailhead, I started the bike and let it idle for a minute, then rolled down hill and snicked it into 1st gear and rode it around until the engine warmed the oil enough to let the clutch release at idle by tapping the brakes.
Within an hour the New Mexico sun had raised the ambient temp by 20 degrees anyway.... Great to live here!
 
Last edited:
Forgot to post this earlier, apparently, when asked about oil.

I talked one of the Rekluse engineers years ago, engineer-to-engineer, about Rekluse and tribology and clutch behaviors I had experienced on a more difficult Rekluse implementation. Out of that conversation
came the admission that "Shell Rotella T4 is a near equivalent to our branded oil" (wonder who supplies that to them?) Their oil could be a touch better than what I have long used, but I've had no reason to find out, as I went with
Rotella T6 long ago and it has worked marvelously with the Rekluse auto clutches.

Shell Rotella is a diesel (more stressed) engine oil that also happens to have the additives conforming to JASO MA2, which is: for modern 4 stroke (gasoline) motorcycle engines that shares engine oil with a wet friction clutch.
There are three Rotellas, varying in base stock. T4 is all mineral or petroleum base stock, T6 all synthetic, and T5 in between maybe half and half. The more the synthetic base stock thew higher the price.
Being a diesel oil gets a really robust anti-wear additive package and longer range. Not that I put long miles between motorcycle oil changes, but I had the stuff around anyway and long used it in all my 4-stroke motos
and ranch ATV.

Those SAE numbers we all know so well - but don't - aren't units of viscosity, but rather represent a range of viscosities reflecting actual viscosity with respect to temperature indirectly. The broader range of the T6 synthetic's
5Winter40 versus the T4's 15Winter40 very indirectly highlights the a higher VI or viscosity index of the synthetic base stock, as in changes in viscosity less over the full operating temperature. Strange, yes? But that's the
bizarre SAE system for describing oil.

SAE number, code for specifying the viscosity of lubricating oil, established by the U.S. Society of Automotive Engineers a long time ago has the numbers for crankcase lubricants range from 5 to 50, and for for transmission
and axle lubricants they ranging from 75 to 250
; the lower the number, the more readily the oil flows. Other than that, the system is, well, confusing, and why you should not buy suspension oils that don't show actual
viscosity at cold and hot temperatures, for example SUS (Saybolt universal seconds).

The 5W part of the oil isn't thinner in viscosity when it's cold than when it's at 100 degrees C and supposedly a 40. It's actual viscosity is the opposite, as in thinner when hot. Anyway, if an oil does not provide a specific
viscosity at both cold and hot temperatures, you can't know the viscosity other than some rough idea from the SAE numbers. 0W20 is thinner than 15W40, but like so many things, it complicated. And I've measured 7W fork oils
that were thicker at room temperature than 10W fork oils.

I don't back off from this thicker diesel oil even in the cold season, as the bike will warm the oil quickly to where it isn't too thick. I've had the clutch on the Beta not release when the bike got cold soaked being pulled on a trailer in 20-degree air.
At the trailhead, I started the bike and let it idle for a minute, then rolled down hill and snicked it into 1st gear and rode it around until the engine warmed the oil enough to let the clutch release at idle by tapping the brakes.
Within an hour the New Mexico sun had raised the ambient temp by 20 degrees anyway.... Great to live here!
But you did! At least some of it.

If tribology standards were created from scratch today, I suspect they'd be a little different, and hopefully less inscrutable.
 
Repeating what I am trying to achieve: I want to bring my personal competition trials bike in line with my other bikes, an auto clutch allowing loss of the manual clutch (and I mean no clutch lever at all), which
allows me to plumb the rear brake direct to any DOT-fluid based clutch master cylinder for a 1-finger strong rear brake. This in turn allows me to lose the foot brake.

The result is an extremely simple controls scheme. Mentally easy to handle and reprogram to, and as my experience has show, increasing both control, confidence, and safety. And zero stall potential!

Both brakes available in an instant, no matter where one's feet happen to be, excellent clutch slipping performance by throttle only that rivals manual control - especially when one gets tired. And this was unexpected:
The rear brake is connected to the 'brain bone' in the same spot as the clutch, and releasing the brake is just like releasing the clutch on an auto clutch bike. Throttle pulse, release clutch (er, um brake), hop
the front wheel or pop up on a step... amazing really.

The only thing missing is no longer important to me: massive-throttle splatters. Can still do them but don't want to. Not needed at the local expert level down.

UPDATE - THIS PROJECT (which was on hold a long while)
Garry Buzelli at EFM auto clutch has experience adapting to conventional helical coil springs clutches, and the newer so-called 'diaphragm' springs clutches are different in significant ways,
like less than half the clutch plates and much higher spring clamping force from the single Belleville spring. A problem, an advantage? I will explore this further.

There is a 2023 Montesa Cota 301RR (blue/white) sitting at the local Honda dealer that I have been eyeing. I know the 4RTs well as I have worked on a number of them from 2005 on. Every time I
ride one I find them weird. I know I could reprogram my soul to one, but don't know how long that would take. A risk that I would not fully mesh with one.

Certainly the engine characteristics of the 301RR would suit auto clutch adoption. And having a conventional clutch lowers implementation risk.
But the cost of commitment to this project going new is steep: A new 2023 301RR in the below color I prefer, sits near me at a Honda dealer of repute $13,500!
$2,000 MORE and one model year older than a new TRS Gold!
Bou on a Blue 2023 301RR.jpg


One concern I had about the 4RT is that unlike the former 315R, the clutch slave cylinder is in on the clutch cover, requiring a 'push in' rather than 'push out' pressure plate, and that require flipping around the clutch hub.
And that I think might complicates auto clutch implementation. If it does, I recently discovered that the the pre-4RT 315R was 'push out' on the pressure plate from the slave cylinder being on the left center case, resulting
the more common 'right side out' clutch hub. Below you can see both the 315R clutch hub and the 4RT clutch hub in their orientations as you would see them looking in. Both appear to have the same 19-tooth spline and spline
diameter, and in the same place relative to the driving transmission shaft. I will find out from Gary if the 315R part would ease auto clutch implementation. At 76 Pounds, worth the buy risk.
315R & 4RT Clutch Hubs.jpg


Will update y'all as I know more. For now, I have a major trials event to go back to working on.
 
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