Madmx
Well-known member
I have a few bucket list bikes. Trials and speedway bikes are about a tie with a slight edge to trials.True machines with a purpose.
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Thinking the Unthinkable - Auto Clutch on a Competition Trials Bike
- Thread starter Motobene
- Start date
Motobene
Well-known member
Speedway has fascinated me since youth, but 'speed' and me don't do well together. I blame that on my plodding brain.
I can't wrap my mind around being propelled down track by a Jawa 884 long stroke motor:
Even worse of being inside the helmet of a Russian doing ice speedway. Nihilism plus total chaos... not my idea of fun!
I can't wrap my mind around being propelled down track by a Jawa 884 long stroke motor:
Even worse of being inside the helmet of a Russian doing ice speedway. Nihilism plus total chaos... not my idea of fun!
Madmx
Well-known member
About 12-15 yrs ago there were speedway and trials bikes in Ohio for $2k. That was back when statewide list compiled Craigslist for the whole state. This was a fast way of finding bikes.
I have also been on the half mile in knobby class. They let a speed way bike in our practice laps. My gas tank still has rock chips. I got showered in limestone gravel. The rider lapped the whole class in 4 laps. It seems trials and speedway bikes are unobtanium in my region now.
I have also been on the half mile in knobby class. They let a speed way bike in our practice laps. My gas tank still has rock chips. I got showered in limestone gravel. The rider lapped the whole class in 4 laps. It seems trials and speedway bikes are unobtanium in my region now.
Nhuskys
Well-known member
We have a speedway track locally. My Yamaha dealer's son races there.
Motobene
Well-known member
Nice blue flame! 100% methanol? Talk about WFO. Quite the opposite of trials.
Regarding the back spray or 'roost', I never liked getting roosted in a race. One thing roost would do is piss me off, increasing focus to chase down the guy who roosted me, do the yelling and throttle blipping intimidation thing, then return the roost on passing the fellow. But I always hated what roost did to my equipment and my bike.
One of my good friends years ago had this hopped up KLX330. He's the definition of competitive. After an Arkansas ride I saw his fancy hopped up KLX. Everything on the front was cracked, broken or shredded. "My God, Bill, what happened!" "Oh, I was just banging bars with a fellow on a KTM 500." Hmm. Expensive fun!
I watched a more recently US speedway race where a substantial rear guard was fit to all the bikes. The usual spray up was knocked down to a few inches.
Regarding the back spray or 'roost', I never liked getting roosted in a race. One thing roost would do is piss me off, increasing focus to chase down the guy who roosted me, do the yelling and throttle blipping intimidation thing, then return the roost on passing the fellow. But I always hated what roost did to my equipment and my bike.
One of my good friends years ago had this hopped up KLX330. He's the definition of competitive. After an Arkansas ride I saw his fancy hopped up KLX. Everything on the front was cracked, broken or shredded. "My God, Bill, what happened!" "Oh, I was just banging bars with a fellow on a KTM 500." Hmm. Expensive fun!
I watched a more recently US speedway race where a substantial rear guard was fit to all the bikes. The usual spray up was knocked down to a few inches.
Madmx
Well-known member
What a primary to clutch then to the rear wheel vs auto whatever I cheeaped out and went mini land. Then ultimate is straight chain off the crank and maintain trail speed. I wanted a scorpa long ride and any trials bike but I missed my prices.
My xt and tw mimick the biggest pigs of a trials bike. My coleman is not to be shaken. I wish trials events were open class. I think trials bikes are total bucket list bikes. And I could store 10 as an investor...haha no dam batteries.
Just so mystified by a trials bike! One day..I will ride and own a scorpa or fanatic, ooh beta or Montessori. TL or TY
My xt and tw mimick the biggest pigs of a trials bike. My coleman is not to be shaken. I wish trials events were open class. I think trials bikes are total bucket list bikes. And I could store 10 as an investor...haha no dam batteries.
Just so mystified by a trials bike! One day..I will ride and own a scorpa or fanatic, ooh beta or Montessori. TL or TY
Nhuskys
Well-known member
Ohio has one of the biggest and most active trials clubs in the country... Trials Inc.
Motobene
Well-known member
I don't remember them all, but the last one was Slavens.
This project shrunk to pfft with a crush of other projects and prep for riding in the jungles of Central America!
This project shrunk to pfft with a crush of other projects and prep for riding in the jungles of Central America!
Motobene
Well-known member
Maybe this one? Jeff futzing with EXP 4.0 in his `24 KTM 500:
Visible right away is the new super-zoot swoopy marketing shape of the 4.0 friction pads.
Visible right away is the new super-zoot swoopy marketing shape of the 4.0 friction pads.
That's the one.
It'd be interesting to see test results covering the improvements in the friction and the EXP rollers. I don't expect Rekluse to release them, though.
I ordered the full CX4 kit and their LH rear brake assembly. I hope my bike's cable clutch won't require much fine tuning while riding.
It'd be interesting to see test results covering the improvements in the friction and the EXP rollers. I don't expect Rekluse to release them, though.
I ordered the full CX4 kit and their LH rear brake assembly. I hope my bike's cable clutch won't require much fine tuning while riding.
Motobene
Well-known member
Congrats on the Rekluse for your CRF450L cable clutch bike!
You chose a more normal path, and like me before you, may you be blessed with learning experiences
The more normal path is the more comfortable in terms of the evolutionary steps... steps of retaining the foot brake with a left hand brake, and retaining the override clutch. I started there too, but then again I'm:
Evolving by logical necessity to increased simplicity, with no override clutch lever and mechanisms, and no foot brake clutter. Just throttle controlling Rekluse clutch and unloading for shifting, and hand brakes. You already know that, but perhaps more 'splanation would help, or at least entertain.
This in my opinion is attaining less from more.
- Plumbing a left-hand rear brake into the master cylinder of the foot brake creates TWO rear brakes, more for the brain to track, and a mini brain freakout if you bumble into using both brakes simultaneously
- When you opt for the auxiliary, versus primary, left hand rear brake, you will by default bypass it and it become at most an 'emergency brake' that won't stay on unless you strap the lever back toward the grip.
Rekluse provides a black dead-engine emergency brake strap with Velcro. but to date I haven't used it once on three Rekluse-equipped bikes
- When you retain an override clutch function on a Rekluse EXP-based system, you will learn quickly to ignore it because it weird and sucks
- You can fine control clutch slip MORE precisely with the throttle on a Rekluse auto clutch than you can with throttle and manual clutch (really), and with a big engine you don't need big clutch dumps to get over stuff
So your current setup may end up to your brain like this electric bike on the left hand:
- Rekluse + cable clutches come with adjustment hassles and inconsistent clutch adjustement
A critical auto clutch adjustment (any type) is the dead engine/idle clutch pack clearance (Rekluse confuses us by calling that 'free play gain'), the newer type EXP-based clutches do not set clearance with shims and such during clutch assembly, but in series with clutch actuation, hydraulic or cable.
With hydraulic clutches Rekluse provides a fine slave cylinder with a setscrew adjuster:
The o-ring-sealed screw creates an adjustable backstop for the piston such that the piston-rod-pressure plate stack-up is always in compression. At dead engine/idle, the pressure plate is lifted off the pack slightly so you can roll the bike around in gear and so at idle the clutch does not roll the bike forward. With EXP stiffer clutch springs are provided and the EXP expands with RPM to get rid of all clearance and then expand against the stiff clutch springs.
On a cable clutch, the only way to to maintain pressure plate lift is tensioning the cable all the time, substantially! On my KLR with EXP Rekuse, the lever was all the way out with cable like a guitar string. Pulling in a clutch lever against a pre-tensioned cable and stiffer clutch springs is yeech! Very weird feeling and if you pull the clutch in any time when the EXP is expanding or contracting, you feel it fighting your hand. Weird! Clutch levers adjusted all the way out is already and ergonomic no-no, promoting 'whiskey clutch', that plus very stiff and the throttle hand causing changes to lever position is just fricken weird!
Now maybe Rekluse has revised this system, but I doubt that's technically possible. Let me know what you get in your 'full CX4 kit.'
Clutch pack clearance is already finicky adjustment and a long cable expanding and contracting with temperature, plus changing tension with steering degrees (recall over tight throttle cables and rpm rise). I hated the feel of the override clutch, and tail chasing the adjustment just pissed me off. The solution was to lose it all except what matters most, a simple and stable way to adjust the clutch pack clearance on a cable clutch bike.
The solution on the KLR turned out very easily made from the tail end of the stock clutch cable:
A short section of the stock cable was brazed to the knurled steel doohickey on the right, but direct to the original steel cable-end adjuster works too, as you don't have to rotate it to adjust it.
Note in the above the brake Speigler line from the handlebar master cylinder direct to the rear caliper zip tied to the non-moving lever.
You can do something similar of the CRF450F:
I advocate for bye bye to all the foot brake clutter too, leaving on the Brembo 10mm DOT fluid clutch master cylinder and custom Speigler brake line. The below cost me $75 used on eBay and I think $70 for the Spiegler line.
...but that's little old me.
End result for me on the left hand was a one-finger-strong rear brake with the lever hydraulically limiting out without sponginess about half way to the bars, just like a hydraulic front brake. That got adopted on my next two bikes
and I'll never go back.
You chose a more normal path, and like me before you, may you be blessed with learning experiences
The more normal path is the more comfortable in terms of the evolutionary steps... steps of retaining the foot brake with a left hand brake, and retaining the override clutch. I started there too, but then again I'm:
Evolving by logical necessity to increased simplicity, with no override clutch lever and mechanisms, and no foot brake clutter. Just throttle controlling Rekluse clutch and unloading for shifting, and hand brakes. You already know that, but perhaps more 'splanation would help, or at least entertain.
This in my opinion is attaining less from more.
- Plumbing a left-hand rear brake into the master cylinder of the foot brake creates TWO rear brakes, more for the brain to track, and a mini brain freakout if you bumble into using both brakes simultaneously
- When you opt for the auxiliary, versus primary, left hand rear brake, you will by default bypass it and it become at most an 'emergency brake' that won't stay on unless you strap the lever back toward the grip.
Rekluse provides a black dead-engine emergency brake strap with Velcro. but to date I haven't used it once on three Rekluse-equipped bikes
- When you retain an override clutch function on a Rekluse EXP-based system, you will learn quickly to ignore it because it weird and sucks
- You can fine control clutch slip MORE precisely with the throttle on a Rekluse auto clutch than you can with throttle and manual clutch (really), and with a big engine you don't need big clutch dumps to get over stuff
So your current setup may end up to your brain like this electric bike on the left hand:
- Rekluse + cable clutches come with adjustment hassles and inconsistent clutch adjustement
A critical auto clutch adjustment (any type) is the dead engine/idle clutch pack clearance (Rekluse confuses us by calling that 'free play gain'), the newer type EXP-based clutches do not set clearance with shims and such during clutch assembly, but in series with clutch actuation, hydraulic or cable.
With hydraulic clutches Rekluse provides a fine slave cylinder with a setscrew adjuster:
The o-ring-sealed screw creates an adjustable backstop for the piston such that the piston-rod-pressure plate stack-up is always in compression. At dead engine/idle, the pressure plate is lifted off the pack slightly so you can roll the bike around in gear and so at idle the clutch does not roll the bike forward. With EXP stiffer clutch springs are provided and the EXP expands with RPM to get rid of all clearance and then expand against the stiff clutch springs.
On a cable clutch, the only way to to maintain pressure plate lift is tensioning the cable all the time, substantially! On my KLR with EXP Rekuse, the lever was all the way out with cable like a guitar string. Pulling in a clutch lever against a pre-tensioned cable and stiffer clutch springs is yeech! Very weird feeling and if you pull the clutch in any time when the EXP is expanding or contracting, you feel it fighting your hand. Weird! Clutch levers adjusted all the way out is already and ergonomic no-no, promoting 'whiskey clutch', that plus very stiff and the throttle hand causing changes to lever position is just fricken weird!
Now maybe Rekluse has revised this system, but I doubt that's technically possible. Let me know what you get in your 'full CX4 kit.'
Clutch pack clearance is already finicky adjustment and a long cable expanding and contracting with temperature, plus changing tension with steering degrees (recall over tight throttle cables and rpm rise). I hated the feel of the override clutch, and tail chasing the adjustment just pissed me off. The solution was to lose it all except what matters most, a simple and stable way to adjust the clutch pack clearance on a cable clutch bike.
The solution on the KLR turned out very easily made from the tail end of the stock clutch cable:
A short section of the stock cable was brazed to the knurled steel doohickey on the right, but direct to the original steel cable-end adjuster works too, as you don't have to rotate it to adjust it.
Note in the above the brake Speigler line from the handlebar master cylinder direct to the rear caliper zip tied to the non-moving lever.
You can do something similar of the CRF450F:
I advocate for bye bye to all the foot brake clutter too, leaving on the Brembo 10mm DOT fluid clutch master cylinder and custom Speigler brake line. The below cost me $75 used on eBay and I think $70 for the Spiegler line.
...but that's little old me.
End result for me on the left hand was a one-finger-strong rear brake with the lever hydraulically limiting out without sponginess about half way to the bars, just like a hydraulic front brake. That got adopted on my next two bikes
and I'll never go back.
Thanks for the help. Your evangelism and some other reviews convinced me to give a Rekluse a try.
Ditching the clutch lever altogether makes sense to me. I may end up doing as you have on your KLR and remove all but a short cable run for clutch adjustment. I'll have to see how well the bike shifts without clutch lever input. Honda may be moving their 450s to hydraulic clutches since the 450RX now comes with one. Being able to use that Rekluse slave cylinder would be better than all the cable faff.
I'll also have to see if I want to remove the rear brake foot control. I like to keep my foot on it at stops on the street, but that behavior can be moved to the left hand.
Ditching the clutch lever altogether makes sense to me. I may end up doing as you have on your KLR and remove all but a short cable run for clutch adjustment. I'll have to see how well the bike shifts without clutch lever input. Honda may be moving their 450s to hydraulic clutches since the 450RX now comes with one. Being able to use that Rekluse slave cylinder would be better than all the cable faff.
I'll also have to see if I want to remove the rear brake foot control. I like to keep my foot on it at stops on the street, but that behavior can be moved to the left hand.
Nhuskys
Well-known member
The EFM is a far superior on a cable application.
Interesting. How so?
If you know of a detailed comparison article or video of the EFM & Rekluse options, I'd like to see it.
Nhuskys
Well-known member
Just my personal experience and that of small group of riders who ran EFM on Italian Husky 125/144/167 small bores. These small displacement bikes still need an active use of the clutch to maintain power and traction. We would add a small coil spring to the cable by the actuating arm, to keep the lever from flopping when clutch wasn't engaged by the rpm's. Lever pull would stiffen as rpm's rose, but lever worked normally.
Thanks. I can see how even small differences and personal preferences would impact a trials bike ridden as intended. For me on my burly CRF450L, those points of finesse may not be as appreciable.
Nhuskys
Well-known member
Large displacement bikes it's just twist and go... or stop!
