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Discussion Starter #1
I needed a damper to meet AHRMA rules. I didn't feel like paying $60.00 (the cheapest) for a Hong Kong period replica. I saw one off a GSXR1000 and thought-- it might just work. Well, despite the crude mounting bracket (one of my old "made in 15 minutes" license plate brackets off a bike I had 30 years ago) and the fasteners dug out of a coffee can, here it is.Most importantly-- it works.

Just thought I'd pass it on. I got this brand new damper off E-Bay for less than $5.00 shipped. New GSXR owners replace em with Scotts or Ohlins and have no use for the stock one.
 

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Discussion Starter #2
Another view. In the end I might blow the budget and get a billet aluminum mount made or, fabricate something out of some angle iron.
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How funny im in the midst of doing the same thing. How is the travel? Pretty good?

can you take some video of you turning the bars?
 

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I concur, I think you need a little better mount. I have a couple of those GSXR1K dampers. Instead of paying big dollars for
Ohlins, Scotts or HyproPro style (I had a Scotts and didn't like it), I drill out the fill plug, drain the oil then use different weight oils to give it different damping. After draining I tap and use a set screw in the hole. I then refill it with 10wt or whatever combination of oils you might need. It works pretty well, I think I have 3 different ones. In reality, I don't change it very much once I have the bike set up. There is one track that's different enough that I change dampers and it's a 10 minute job on my GSXR1K.
 

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Discussion Starter #5
Dirtbag said:
How funny im in the midst of doing the same thing. How is the travel? Pretty good?

can you take some video of you turning the bars?
I'll try. I have full travel but, you might be able to see, I've added 7mm (about 1/4 inch) to the stops (another AHRMA rule to keep your hands, when on the grips, 1 inch from the tank).
 

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i have been considering one of these for my 500 project. the new gsxrs have a hydraulic/electric proportional valve as well to adjust the dampening characteristics depending on speed i believe.

post a video of range of motion when you get a sec.
 

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Question...I've never ridden a bike with a damper, so what effect do they have? Are they just for high-speeds? Is this overkill for around town riding? Just wondering if its worth my wild to work out something while I have the bike apart now.
 

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Not that I'm some great craftsman but....that bracket is going to bend. Do you really want to be messing with your steering abilities while underway ?
 

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Perhaps I am misguided in the "proper" set-up for that particular damper,
but as I understand their workings, shouldn't the bolt it pivots on essentially
be parallel to the shaft-end pivot bolt?..... I would think that mounting it
with the triangular "tab" oriented more horizontally would be the way to go...
??????... Just my opinion.... Steve
 

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dampers can do a great deal to tame evil handling, tankslapers and the like. if they are set up well then you don't even know they are there. I have one on my 04 speed triple and it does wonders for driving hard out of corners and for cornering hard in suspect conditions. tar strips, rough pavement, gravel etc.. much more important on bikes with steep rake and short trail figures though.
 

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66Sprint said:
Perhaps I am misguided in the "proper" set-up for that particular damper,
but as I understand their workings, shouldn't the bolt it pivots on essentially
be parallel to the shaft-end pivot bolt?..... I would think that mounting it
with the triangular "tab" oriented more horizontally would be the way to go...
??????... Just my opinion.... Steve
i am having a hard time visualizing what you're suggesting, but as long as it's a solid rod if it doesn't bind, it should work fine. The direction of dampening wouldn't matter as long as there's enough range of motion to prevent binding. The two link points will work themselves out to be a straight line from the design.



Attached are the new GXR style with a valve on it. Anyone know more about them to confirm dynamic operations based on speed?
 

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Jason... Yes I understand that, BUT, If both mounting "bolts" are parallel and set at the same height *, the unit simply arcs within that one plane, rotating on the pivots... As he has it mounted, there is a huge amount of tortional force (twisting) on both pivots.... The front is a ball joint, so no problem there, but the frame-side pivot is forced (twisted)against the damper and will wallow/wear the damper body and bolt...(in his pic, the rear bolt is twisted and almost binding on the body of the unit)...Also, as shown, the rod would project rearward and possibly strike other components...Since the rod's path is only controlled by the position the damper body was 'left" in (where ever it 'flopped' after the last "bump"), this path can randomly occur anywhere within a semi-flattened conical area..... (my method only allows motion along one finite line) .....On a "shock type" damper, this would/can be nominally acceptable as there is no rod projecting aft of the mount point to cause any damage.
Basic engineering stipulates that the simpler the motion required, the less complex the stresses, the more efficient the machine.
Was this enough of a "word picture", or should I attempt to draw it up and post?
:shock: ... ;) Steve


* By "set at the same height" I mean in a plane parallel to the one ascribed by the bottom of the lower tree as it rotates.

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66Sprint said:
Jason... Yes I understand that, BUT, If both mounting "bolts" are parallel and set at the same height *, the unit simply arcs within that one plane, rotating on the pivots... As he has it mounted, there is a huge amount of tortional force (twisting) on both pivots.... The front is a ball joint, so no problem there, but the frame-side pivot is forced (twisted)against the damper and will wallow/wear the damper body and bolt...(in his pic, the rear bolt is twisted and almost binding on the body of the unit)...Also, as shown, the rod would project rearward and possibly strike other components...Since the rod's path is only controlled by the position the damper body was 'left" in (where ever it 'flopped' after the last "bump"), this path can randomly occur anywhere within a semi-flattened conical area..... (my method only allows motion along one finite line) .....On a "shock type" damper, this would/can be nominally acceptable as there is no rod projecting aft of the mount point to cause any damage.
Basic engineering stipulates that the simpler the motion required, the less complex the stresses, the more efficient the machine.
Was this enough of a "word picture", or should I attempt to draw it up and post?
:shock: ... ;) Steve


* By "set at the same height" I mean in a plane parallel to the one ascribed by the bottom of the lower tree as it rotates.

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i understand now. You're looking for the side tang to be a more ridged mount and to be parallel with the ball join mount on the tree. I think. I agree the tang is taking too much load and radially loading the damper rod.

Jason
 

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Yep, I follow the K.I.S.S. Principle.......LOL...
Funny how we can picture things in our brains, yet often words fail to convey that exact picture to others.....
Sorry I have no familiarity with either unit, so am unable to help assess its usage in your application. It APPEARS to me to be electrically controlled by a solenoid valve, so I'm ASSUMING that the bike would require a trigger switch in either the tach (probably electronic already) or in the speedo....
I'd have to guess Tach..........
Steve
 

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66Sprint said:
Yep, I follow the K.I.S.S. Principle.......LOL...
Funny how we can picture things in our brains, yet often words fail to convey that exact picture to others.....
Sorry I have no familiarity with either unit, so am unable to help assess its usage in your application. It APPEARS to me to be electrically controlled by a solenoid valve, so I'm ASSUMING that the bike would require a trigger switch in either the tach (probably electronic already) or in the speedo....
I'd have to guess Tach..........
Steve
Agreed. I am unfortunately very used to using inventor/solid works and drawing arrows to my 'issues' with designs. Somehow descriptions can escape the concepts easily.




My company tests a lot of those types of products, hydraulic solenoid valves, and I want to say it's a proportional relief valve, so that with a PWM command, you can change the dampening characteristics of it, but it could also be on on/off valve for two different settings (stiff/and not so stiff). I had heard that the newer R1's have some 'mode' settings for race, road, and something like this would play into that, but it's not an R1... just curious if anyone has an experience with it.
 

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JeyLux said:
I had heard that the newer R1's have some 'mode' settings for race, road, and something like this would play into that, but it's not an R1... just curious if anyone has an experience with it.
I hadn't heard about variable damping on the R1 but the newer Honda CBR1000RR's had/have an HESD (Hydraulic, Electronic, Steering, Damping) device that works pretty well.

On newer bikes most headshake is due to improper tire pressures or improper chassis set up. Unless you're racing something in a vintage class I haven't seen the need for a damper on any of the classics I've ridden recently. But, I haven't ridden over any pot holes or rough roads at speed either.
 

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ihatespeed said:
dampers can do a great deal to tame evil handling, tankslapers and the like. if they are set up well then you don't even know they are there. I have one on my 04 speed triple and it does wonders for driving hard out of corners and for cornering hard in suspect conditions. tar strips, rough pavement, gravel etc.. much more important on bikes with steep rake and short trail figures though.
The "much more important on bikes with steep rake and short trail figures though." part I'm in total agreement with....Having set-up many bikes (350's up) with early (77/78) 750 F forks in 550 trees (less forward offset, which reduces trail, especially when combined with the smaller 18" wheel), I LIKE having a damper installed.......... A much more "secure" feeling when "driving hard"......JMHO.... Steve
 

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Discussion Starter #19
RicH2 said:
Not that I'm some great craftsman but....that bracket is going to bend. Do you really want to be messing with your steering abilities while underway ?

I guess I didn't make it clear. This is just a temporary set up to get the right location. Of course I'm not going to use an old rusty piece of metal for a bracket or, a toilet seat brass bolt to hold it to the frame. Although, that bracket is plenty strong enough!

My final design is not 100% decided but, I'm planning on drilling out the rectangular tab at the bottom of the head stock (this is going to need another drawing, I'm sure) and, using an "L" shaped bracket made from aluminum or steel, bolt the small end of the "L" to the tab, the long end to the through tube (what is that for anyway? For that matter, what is that rectangular tab below the headstock for-- a previous design left over for a steering lock??) and then, the end of the long end of the "L" to the damper. I will need a spacer to make it stand away from the frame or, make an "S" bend in the bracket. I may move it up slightly but have to allow for the gas tank. As it is, the damper is only about 15 degrees off parallel to the lower triple clamp. The frame is sitting back on it's haunches, resting on the swing arm so, it looks like much more of an angle than it will be once the bike is on it's wheels.
Still trying to get up the ambition to video the travel. Right now, it's a smooth resistance through out the travel with about 3/8" or more of the damper rod exposed at each end when it hit's the stops. Remember-- I decreased the lock to lock radius by adding 7mm of weld! If I remember right, I ran out of damper rod travel with the stock steering stops.
 

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Discussion Starter #20
66Sprint said:
ihatespeed said:
dampers can do a great deal to tame evil handling, tankslapers and the like. if they are set up well then you don't even know they are there. I have one on my 04 speed triple and it does wonders for driving hard out of corners and for cornering hard in suspect conditions. tar strips, rough pavement, gravel etc.. much more important on bikes with steep rake and short trail figures though.
The "much more important on bikes with steep rake and short trail figures though." part I'm in total agreement with....Having set-up many bikes (350's up) with early (77/78) 750 F forks in 550 trees (less forward offset, which reduces trail, especially when combined with the smaller 18" wheel), I LIKE having a damper installed.......... A much more "secure" feeling when "driving hard"......JMHO.... Steve

After attending a few vintage races and strolling the pits, I have noticed that it is the front tire that takes the brunt of the abuse. Like Steve says, the more "relaxed" rake on the older bikes is not conducive to turning. I have noted (considerably so after stepping off a modern sport bike) that this dang thing DOES NOT want to turn! Front end push is pretty much a constant. The majority of the vintage racers have dropped their front ends by about 10mm or so. Some more, some less in an effort to decrease the rake and getting the bike to turn.
For the street, it's no biggy but, for those of you that like the twisties, you might consider dropping the front incrementally. The more you drop it, the more twitchy it will get-- just be aware!

This:
"with early (77/78) 750 F forks in 550 trees (less forward offset, which reduces trail, especially when combined with the smaller 18" wheel),"
Just sank in.

More helpful info! But also--MO MONEY!! MO MONEY
(thanks Steve!)
 
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