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This has been discussed before.
I don't know if anyone has had actual problems, but the potential exists.
For what it's worth, I've got an '07 ABS bike with 56,000 miles. The last 40,000 of which have been with a Superbrace fork brace and heavier-than-stock fork springs.
Even with the fork tubes raised about 10mm, and doing some occasional rough gravel roads, I haven't even come close to contact.
Hope this helps.
Norm
I don't know if anyone has had actual problems, but the potential exists.
For what it's worth, I've got an '07 ABS bike with 56,000 miles. The last 40,000 of which have been with a Superbrace fork brace and heavier-than-stock fork springs.
Even with the fork tubes raised about 10mm, and doing some occasional rough gravel roads, I haven't even come close to contact.
Hope this helps.
Norm
I have the same setup as you, and the same concern, so about a year ago I put a nylon zip-tie on the fork tube to see just how far the suspension would actually compress. After a year of riding I can confirm that the fork brace never came close enough to contact the ABS junction block, but it was obvious that it was hitting that hose on the left hand side - never to the point of turning the banjo, but still not good.
My quick fix was to loosen the banjo bolt and rotate the hose out of harms way. There is sufficient length to do this without any fear of kinking the hose at full extension. Now the worst that can possibly happen is two pieces of dumb metal making contact - the fork brace and the ABS junction block - and I can't see that doing anything more than scuffing a bit of paint.
My forks are raised about 5/8" (16 mm) BTW.
My quick fix was to loosen the banjo bolt and rotate the hose out of harms way. There is sufficient length to do this without any fear of kinking the hose at full extension. Now the worst that can possibly happen is two pieces of dumb metal making contact - the fork brace and the ABS junction block - and I can't see that doing anything more than scuffing a bit of paint.
My forks are raised about 5/8" (16 mm) BTW.
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BobA
I have a 07 DL650A. I've raised the forks about 12 mm and installed a forkbrace. Over past 4K miles no problems. I did the zip-tie test myself and feel confident that there is enough margin remaining to prevent any contact.
You might try taping a piece (~ 15 mm) of styrofoam to the bottom of the ABS unit (or top of the forkbrace) and then drive over some larger than normal street bumps to see if there is any contact betwixt :beatnik: the styrofoam and the ABS unit.
Your concern is a valid one. Fortunately the problem hasnt reared its ugly head for anyone that I know of.
PS... I used to live in Asbury Park while stationed at Ft. Monmouth in the early seventies. Spent almost every Saturday riding through the pine trails thereabouts. Good times!
I have a 07 DL650A. I've raised the forks about 12 mm and installed a forkbrace. Over past 4K miles no problems. I did the zip-tie test myself and feel confident that there is enough margin remaining to prevent any contact.
You might try taping a piece (~ 15 mm) of styrofoam to the bottom of the ABS unit (or top of the forkbrace) and then drive over some larger than normal street bumps to see if there is any contact betwixt :beatnik: the styrofoam and the ABS unit.
Your concern is a valid one. Fortunately the problem hasnt reared its ugly head for anyone that I know of.
PS... I used to live in Asbury Park while stationed at Ft. Monmouth in the early seventies. Spent almost every Saturday riding through the pine trails thereabouts. Good times!
Thanks for the input.
I suspect that you are correct that under normal (or even pretty rough) usage contact is unlikely, but I'm just wondering what might happen in case of an emergency stop. I don't know how far the forks would compress. It would be pretty unfortunate (to say the least) if at the moment of maximum braking (and maximum fork compression), the ABS cylinder or a hose hit the fork brace and sheared off, resulting in a loss of the front brakes!
Thanks for the tip about rotating the banjo on the hose on the left of the ABS cylinder. I'll take a look at that. If that was out of the way it would give about another1/2" of travel before anything contacted.
I wonder what kind of force you need to fully compress the forks? Get the thing airborn and land on the front wheel maybe? I really don't think I want to test what the ultimate limits of fork compression are unless I have to!
I suspect that you are correct that under normal (or even pretty rough) usage contact is unlikely, but I'm just wondering what might happen in case of an emergency stop. I don't know how far the forks would compress. It would be pretty unfortunate (to say the least) if at the moment of maximum braking (and maximum fork compression), the ABS cylinder or a hose hit the fork brace and sheared off, resulting in a loss of the front brakes!
Thanks for the tip about rotating the banjo on the hose on the left of the ABS cylinder. I'll take a look at that. If that was out of the way it would give about another1/2" of travel before anything contacted.
I wonder what kind of force you need to fully compress the forks? Get the thing airborn and land on the front wheel maybe? I really don't think I want to test what the ultimate limits of fork compression are unless I have to!
I'm not against a small limit on fork travel, it's just that I'd rather not use the ABS brake hoses as stops! I suppose the alternative might be to actually mount some hard rubber stops that limited fork compression before it reaches the ABS junction assembly. I'm sure that bike has more fork travel than I will actually need. I just don't like the idea that the ultimate stop is part of my front brakes!
It does happen and it's not very nice: 2009 ABS Front Brake Loss
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This lack of clearence will affect dirt rider more than pure paved road rider.
things u can do to reduce / minimise the impact:
first of all - total fork compression and extension travel due the wheels own weight acting on top-out springs is only 139mm and NOT 150mm as Mr suzuki advised.
Second, rotate the banjo bolt and rotate anti-clockwise by about 30 degrees will ensure the only contact is between brace and ABS block. now re-measure the clearance, see link for one of the possible methods
third, limit amount of raising forks to 5-10mm only, depending the brand of brace u use and where the brace sit on the fork outers.
If the lack of clearance is more than 5mm, i would be worried about the impact of 2 metals would carry too much energy to do some serious damage.
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This lack of clearence will affect dirt rider more than pure paved road rider.
things u can do to reduce / minimise the impact:
first of all - total fork compression and extension travel due the wheels own weight acting on top-out springs is only 139mm and NOT 150mm as Mr suzuki advised.
Second, rotate the banjo bolt and rotate anti-clockwise by about 30 degrees will ensure the only contact is between brace and ABS block. now re-measure the clearance, see link for one of the possible methods
third, limit amount of raising forks to 5-10mm only, depending the brand of brace u use and where the brace sit on the fork outers.
If the lack of clearance is more than 5mm, i would be worried about the impact of 2 metals would carry too much energy to do some serious damage.
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I was practicing my braking last year in an empty parking lot and lost my front brakes because of contact between the left hose and the Superbrace. Forks were raised 15mm. It turned the hose counter clockwise enough to lossen and lose my front brakes completely. I ended up setting my forks up to 8mm.
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Did you happen to have any of your "little ladies" on the back at the time?
Total loss of front brakes as reported here by two riders is exactly what I'm worried about.
I wrote to Rick and he acknowledged the problem. It's all very well to say that it's documented on forums, but if you buy a product it should come with some sort of instructions and warnings that you may kill yourself using it! The brace comes with no instructions and no hint that under certain conditions it can cause full loss of front brakes on an ABS bike. I'd have thought that even if only to prevent being sued anyone selling fork braces would include a warning and a disclamer. You could get yourself in a lot of trouble selling an aftermarket part that resulted in a rider's death.
Rick said I could send the fork brace back, which I may well do, but it would have been nice to know about this BEFORE ordering and it would have been nice to be forwarned of the problem. I'm certain that not everyone who buys one of these braces (or any other brace) crawls under the bike and measures the minimum clearance under full fork compression or scours the forums to see if there's some sort of problem with it. Obviously the riders who reported total front brake failure didn't.
Greywolf - I presume you cut the gaiters because there's no way you can fit them around the lower forks with the brace attached? I guess even with no lower attachment point they do protect the fork tubes and it looks like they might limit fork travel under full compression. Any idea how much they do limit the travel (i.e. their length under full compression)?
I wrote to Rick and he acknowledged the problem. It's all very well to say that it's documented on forums, but if you buy a product it should come with some sort of instructions and warnings that you may kill yourself using it! The brace comes with no instructions and no hint that under certain conditions it can cause full loss of front brakes on an ABS bike. I'd have thought that even if only to prevent being sued anyone selling fork braces would include a warning and a disclamer. You could get yourself in a lot of trouble selling an aftermarket part that resulted in a rider's death.
Rick said I could send the fork brace back, which I may well do, but it would have been nice to know about this BEFORE ordering and it would have been nice to be forwarned of the problem. I'm certain that not everyone who buys one of these braces (or any other brace) crawls under the bike and measures the minimum clearance under full fork compression or scours the forums to see if there's some sort of problem with it. Obviously the riders who reported total front brake failure didn't.
Greywolf - I presume you cut the gaiters because there's no way you can fit them around the lower forks with the brace attached? I guess even with no lower attachment point they do protect the fork tubes and it looks like they might limit fork travel under full compression. Any idea how much they do limit the travel (i.e. their length under full compression)?
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I haven't measured the travel available. I know I want the gaiters there protecting the forks and that takes precedence for me. I've never gotten an abrupt hit on the front so it shouldn't be much. Black Lab has measured it. As far as the fork brace goes, I think we all should use one. I stuck a DL1000 tire between my feet and wiggled the handlebars. I could see the fender move back and forth over the tire. A fork brace in a stock bike will not hit the ABS junction. The forks have to be moved up in the triple clamps to do that and that's the rider's responsibility. I was interested to see Suzuki changed the brake plumbing around for the 2012 bike and there is no longer a junction under the triple clamp.
I have an 11 650 ABS, and one of Rick's fork braces in the mail. This thread has caused me some concern, but GW's last post about the brace not hitting the ABS set-up on a non-lowered (stock) wee has provided comfort.
While I have no plans to lower the forks (even less so now), does anyone think it's worth adjusting the banjo bolt/brake line as suggested in some of these posts, as an extra preventative measure? If so, will loosening the bolt to turn it anti-clockwise the suggested 30 degrees (and then tightening it) cause any issue with leaking brake fluid of air getting in there? this might be a stupid question, but please humour me.
Thanks in advance,
Dave
While I have no plans to lower the forks (even less so now), does anyone think it's worth adjusting the banjo bolt/brake line as suggested in some of these posts, as an extra preventative measure? If so, will loosening the bolt to turn it anti-clockwise the suggested 30 degrees (and then tightening it) cause any issue with leaking brake fluid of air getting in there? this might be a stupid question, but please humour me.
Thanks in advance,
Dave
I rotated my banjo bolt with no problem. Loosen it just enough to be able to rotate it, then tighten it back up. You shouldn't lose any fluid or let any air into the system that way. The line doesn't seem to be overly streched by doing this.
With the forks at stock height and the banjo bolt rotated you should have close to ~145mm of fork travel before the brace hits the ABS coupling body. That's less than the fork travel that Suzuki specify (150mm) but more than some people report that the maximum fork travel actually is (~140mm). However my measurements still suggest that under full fork compression, and assuming that the travel is only 140mm, you'll still hit the left brake hose coupling unless you rotate that banjo bolt. It looks to me like you only have around 133mm of clearance with that hose in the stock position. Of course my measurments cound be off by a few mm, but even so it's very close. Too close for comfort.
It would still be nice if the brace actually came with a warning about all this! At least a comment about not lowering the forks if the brace is used and rotating the left ABS brake coupling.
It would be interesting to read of changes in handling related to (a) raising the forks, (b) adding the brace and (c) doing both. I just wonder if raising the forks and adding the brace both address some of the same issues. Raising the forks would tend to lower fork flex since the fork length below the bottom tripple tree would be shorter. The fork brace also reduces fork flex of course, and would do a better job of it.
With the forks at stock height and the banjo bolt rotated you should have close to ~145mm of fork travel before the brace hits the ABS coupling body. That's less than the fork travel that Suzuki specify (150mm) but more than some people report that the maximum fork travel actually is (~140mm). However my measurements still suggest that under full fork compression, and assuming that the travel is only 140mm, you'll still hit the left brake hose coupling unless you rotate that banjo bolt. It looks to me like you only have around 133mm of clearance with that hose in the stock position. Of course my measurments cound be off by a few mm, but even so it's very close. Too close for comfort.
It would still be nice if the brace actually came with a warning about all this! At least a comment about not lowering the forks if the brace is used and rotating the left ABS brake coupling.
It would be interesting to read of changes in handling related to (a) raising the forks, (b) adding the brace and (c) doing both. I just wonder if raising the forks and adding the brace both address some of the same issues. Raising the forks would tend to lower fork flex since the fork length below the bottom tripple tree would be shorter. The fork brace also reduces fork flex of course, and would do a better job of it.
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As far as I can tell, a big benefit in lowering the front is aerodynamics. The lower angle of attack keeps the front end from lightening at higher speed and makes the bike more stable at such speeds. That's the opposite of what would be expected from a change in chassis geometry alone and an often reported result. I found the idea of lowering the front causing an increase in stability impossible until I tried it and found it to be true. The only reason I could think of is aerodynamic. I like the quicker steering too.
It's hard to belive that a small fork lift would change aerodynamics much. First a 12mm lift only changes the "angle of attack" by about 0.5 degrees and second, the flow around the fairing is pretty turbulant and so would be fairly insensitive to changes in angle.
However, if it works, it works, however it does it!
I suspect that small airfoils on the front forks (in clean air) would have a much larger effect on front end loading. Even changing the size and angle of the windscreen would probably have more effect than a small change in the fairing angle. A small screen angled back might well generate less lift on the front than a larger screen at a more upright angle. Just a guess there though.
However, if it works, it works, however it does it!
I suspect that small airfoils on the front forks (in clean air) would have a much larger effect on front end loading. Even changing the size and angle of the windscreen would probably have more effect than a small change in the fairing angle. A small screen angled back might well generate less lift on the front than a larger screen at a more upright angle. Just a guess there though.
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I run 4 different windscreens. Aerodynamics is a guess as I don't have a wind tunnel, but dropping the front end 10-15mm with the back stock results in a much more stable high speed ride around trucks and wind gusts as well as more agility at lower speeds. I tell people to try it and see if it works for them. Most like it, a few don't.
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