gregjet Posted February 25, 2017 Share Posted February 25, 2017 OK here us something I have been thinking about for some time. i ride mountain bikes and motorcycles. One thing about MTB's is having the rear brake on the handlebar allows MUCH finer control of the braking. On a motorcycle that would be advantageous enough but it would also allow you to keep the rear brake on if you are stopped on a slope. It also means when you are leant over on the right side you have full control for trail braking when you foot is up to stop it scrapeing. Most conversions from the the foot brake are to a thumb brake. My preference is for a thumb clutch and a finger brake . For the added reason that it requires no adaptation from the MTB to the motorcycle for brake control. PLEASE don't tell me why it is a bad idea nor that it won't work because that's how I ride most of the time on the MTB. It also has a thumb control for the front chainring gear change which works in a similar way to what I expect a clutch would including the amount of throw and force needed. Has anyone heard of such a successful conversion already? It is on my list of things to fabricate, but a long way down at the moment. Any constructive ideas would be welcome. Go forth and modify my son...go forth and modify... Link to comment Share on other sites More sharing options...
letitsnow Posted February 25, 2017 Share Posted February 25, 2017 Some people add an auto clutch and then a left hand rear brake on their offroad bikes - that might be another option? Link to comment Share on other sites More sharing options...
rick Posted February 25, 2017 Share Posted February 25, 2017 Guess you could try to convert a clutch pump from another bike into a brake lever for the left side. As for operating the clutch with your left thumb, closest thing I can think of is a shifter for a bicycle like Shimano RapidFires - you'd have to eliminate any detents or watching mechanism, but that would allow you to use your thumb. Makes my left thumb hurt just thinking about it. Link to comment Share on other sites More sharing options...
stickshift Posted February 25, 2017 Share Posted February 25, 2017 I think a cable operated thumb clutch may not be feasible, you might not get the leverage to operate it effectively. If you converted your clutch to hydraulic operation you could use an aftermarket thumb brake to operate it. Not sure that the clutch can be converted to hydraulic; you would need to rely on aftermarket parts or compatible oem parts from other models. I converted a honda cable clutch to hydraulic in the past, but that was using oem parts from a different model. I'm pretty keen to fit a thumb operated rear brake to the 07 (plenty of aftermarket options available), that doesn't help you though! Edit: check out PFMs twin master cylinder setup, a multi-functional thiing of beauty!http://www.west-performance.com/services/pfm-brakes/ This would work: https://www.amazon.com/Frando-Motorcycle-Hydraulic-Cylinder-Universal/dp/B016ZC3XR8 Link to comment Share on other sites More sharing options...
rick Posted February 25, 2017 Share Posted February 25, 2017 I wasn't suggesting to convert the clutch to hydraulics. I was just thinking of using a hydraulic clutch's lever and pump to operate the rear brake. Thought that's what gregjet was getting at. Link to comment Share on other sites More sharing options...
stickshift Posted February 26, 2017 Share Posted February 26, 2017 I wasn't suggesting to convert the clutch to hydraulics. I was just thinking of using a hydraulic clutch's lever and pump to operate the rear brake. Thought that's what gregjet was getting at. I get that, that's the easy bit. Finding a solution to relocate the clutch so that it's effective is the harder part. Cable operation is out of the question in my opinion, hence the need to convert to hydraulic. The PFM twin master cylinder above would allow you to use the outboard lever for clutch (more leverage/ hydraulic pressure) and inboard for rear brake. A pretty neat solution. Link to comment Share on other sites More sharing options...
rick Posted February 26, 2017 Share Posted February 26, 2017 So 2 master cylinders and hoses on the left bar? Just converting to hydraulics won't necessarily result in a lighter pressure. Piston diameters, length of throw for both the master and slave complicate matters. My Aprilia's stock slave cylinder is a left-handed workout in traffic. The aftermarket slaves have bigger diameters for a lessoned lever force, but that results in a loss of throw that must be made up for by moving the adjustable clutch lever must well out from the bar to push more fluid. W/o that compensation, shift quality is lost and finding neutral after a complete stop can become a challenge. I dunno - seems easy enough to me to just use the right foot on the brake lever to prevent roll-backs. we have plenty of really steep hills here. I do this all the time. Link to comment Share on other sites More sharing options...
gregjet Posted February 27, 2017 Author Share Posted February 27, 2017 I actually have a heap of thumbshifters from older shimano front chainring setups sitting around. The lever load on then is actually quite high in their original function, so they are up to the task strength wise. Activation ratios are the key to any success. . The lever ratios are the key and whether sufficient force AND sensitivity can be had to operate the clutch throwout lever. I guess a servo assist IS possible, but I intend to go the way of activation input /output lever lengths and ratios initially. Basically I really like the sensitivity of both brakes on the handlebars and all the necessary stuff is easy and available. The biggie is the clutch. I have NOT ruled out an automatic clutch conversion but I do like a good action manual clutch particularly when grip conditions are less than ideal. Auto would be a last resort. Certainly wouldn't consider it if I was racing. Rick are you in a left hand drive country. Often I find the road camber can make it so you have to put your right foot down. This thread is primarily here as a thought experiment to see if any good ideas turn up. Go forth and modify my son...go forth and modify... Link to comment Share on other sites More sharing options...
rick Posted February 27, 2017 Share Posted February 27, 2017 Nope we drive on the proper, erm, right side of the road here in pennsylvania. heh, heh. But good point on the camber. I have a 200 mile loop I like to do. There's a spot where I have to stop facing uphill at an intersection to turn left with a road that drops seriously to my right. It's not a big deal on the FZ, but on my Futura where the seat is taller and wider and the bike weighs - well, another me more, I have to be really careful as my right foot can't come close to touching the ground. If I don't make a conscious effort to have the bike settle to the left, I'm going down. And man would that be ugly trying to pick up a heavy (top heavy too) with the wheels now uphill of the bars. If you can eliminate the friction mechanism inside those shimano levers meant to hold the chain on a chainring, that would be yer easiest way. That you have sitting about, the cheapest as well. You'll also have to modify where the cable end fits as the bicycles stuff is all way smaller as well as a different shape. Too bad there's no quick shifter option for this bike (or is there?) That won't negate the need for a clutch lever, but would sure cut down on how many times you had to use yer thumb. Link to comment Share on other sites More sharing options...
Premium Member botticelli Posted February 27, 2017 Premium Member Share Posted February 27, 2017 If your really set on it, then yes use a clutch master cylinder as a hydraulic rear brake. Then make your right foot the clutch. It should be easy to operate a cable pull with the foot lever. Just an idea.... Personally, I ride road and mountain bikes to keep me trim and I never find an issue, but I do know may ppl that do. The usual fix is to swap your brakes on your pedal bikes to match your moto. Keep us posted. '16 FZ07 Link to comment Share on other sites More sharing options...
gregjet Posted February 27, 2017 Author Share Posted February 27, 2017 Rick, Quickshifter or not you still need a clutch for stopping and starting and slipping when necessary. I can prob fabricate a bespoke lever easy enough, probably on the lines of the Shimano action. That way may be even able to use the stock clutch cable? Because it only needs to pull in and lapse out shouldn't be too difficult. Again it will be all about the lever ratios and the action orientation as well. Ergonomically the most natural action for the thumb is outwards so I might play with some wood or plastic mock ups first. Go forth and modify my son...go forth and modify... Link to comment Share on other sites More sharing options...
rick Posted February 28, 2017 Share Posted February 28, 2017 Should be interesting to see what you come up with. Damaged the big knuckle on my left thumb years ago. It's about 25% bigger than the same on my right hand all the time. Like I said, this conversation makes my thumb hurt just thinking about it. Hmm, how hard would it be to put a throttle grip on the left side and use a twist to operate the clutch? Heh, heh. Just kiddin. Link to comment Share on other sites More sharing options...
pattonme Posted February 28, 2017 Share Posted February 28, 2017 the solution is obvious! http://s.hswstatic.com/gif/1940-indian-440-2.jpghttp://www.clubchopper.com/forums/attachments/shop-talk/16433d1138200577-jockey-shift-clutch-lever-155-2.jpg ok, fine....in proper seriousness:http://www.disabledmotorcyclerider.com/klever.html http://www.disabledmotorcyclerider.com/klever2/wp17cc7fe0_00.jpg Link to comment Share on other sites More sharing options...
rick Posted February 28, 2017 Share Posted February 28, 2017 Linked brakes at its simplest. Link to comment Share on other sites More sharing options...
gregjet Posted February 28, 2017 Author Share Posted February 28, 2017 Rick, I am a strong user of the brakes for balance so use the front and rear separately a lot. When you are on the edge ie. going hard OR is tricky conditions like very wet roads, ice etc. I often use the rear only as a engine moderator rater than the throttle. Same with trickling especially turning at very low speed. Thank pattonme. I have seen that one. I am aiming at using different finger/thumb for different functions. Helps keep the brain confusion lower in panic situations ( plus it is more like the mtb use which I am use to). I alredady know about the Clake as the fastest guy at our track ( not Jack Miller but a national level motard rider) was the Aussie national front man for them. It is what got me started thinking about the change. Go forth and modify my son...go forth and modify... Link to comment Share on other sites More sharing options...
Global Moderator sorkyah Posted March 5, 2017 Global Moderator Share Posted March 5, 2017 How about just running solid lines with a proportioning/metering valve, similar to a car. And inline somewhere have a ball valve to switch the rear to the foot pedal when you want it independent ATGATT... ATTATT, two acronyms I live by. Link to comment Share on other sites More sharing options...
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