I looked in the owners manual in .PDF form and there is nothing in it mentioning how to adjust the rear shock and using the search function in Adobe the word shock doesn’t come up at all. There is also no mention of rear shock adjustment what so ever in the service manual but on page 18-13 there is a “SHOCK ABSORBER DISPOSAL PROCEDURE” that is very interesting and looks like a recipe for disaster. I looked on http://www.hondaprokevin.com/2018-h...ecs-automatic-motorcycle-ctx-700-touring-bike which has the most detailed specs and descriptions of the CTX and could find no mention of an adjustable rear shock. If you click on the link and scroll down there are some beautiful cutaway pics of the innards of the DCT. I don’t think Honda had any intention of an adjustable rear shock or they would have used it as a selling point in their advertising or put it on the specs sheet. I think the Honda designers would tell you that the shock is not designed specifically to be adjustable although the way SHOWA designed the threaded spring retainers it is possible to dial in a little more spring preload. I agree 100% with Mr. Moors assessment “You can set sag all you want, but if the spring rate is wrong for the load then it is wrong and sag isn't going to be more than a small band-aid on a wound that never heals. Spring preload adjustment is for making minor changes in ride height when there are modest changes in load, it doesn't replace getting the proper rate spring”.
Trouble in Paradise.
- Thread starter randy1149
- Start date
Steven
Member
Actually, for me, sag made a huge difference even with the oem, but consider that in stock form and setting, I had only one inch of wheel travel available so I bottomed out quite often. Setting sag allowed me 3 inches of travel and that was huge in comparison.
I was going to do this big write up about why setting sag is the most important thing you can do to your bike, any bike, but you folks already know these things, no sense preaching to the choir...
Using an after market spring can also help to some degree, but it's still a band aid if the shocks compression and damping isn't adjusted for the bike and the rider. Keep in mind that with an after market shock there are different compression dampings for both low and high speed, so it's possible tailor the shock for different road conditions or ride preferences, but the oem doesn't have this capability.
The oem shock on the CTX is a one size fits all and in my opinion low quality. I think it works just fine for lighter riders, but for heavier riders or two up, it's almost useless depending on road conditions. This doesn't mean that a heavier person can't ride in comfort, but it does mean that that rider has to be a little more careful what roads they take.
Just saying...
I was going to do this big write up about why setting sag is the most important thing you can do to your bike, any bike, but you folks already know these things, no sense preaching to the choir...
Using an after market spring can also help to some degree, but it's still a band aid if the shocks compression and damping isn't adjusted for the bike and the rider. Keep in mind that with an after market shock there are different compression dampings for both low and high speed, so it's possible tailor the shock for different road conditions or ride preferences, but the oem doesn't have this capability.
The oem shock on the CTX is a one size fits all and in my opinion low quality. I think it works just fine for lighter riders, but for heavier riders or two up, it's almost useless depending on road conditions. This doesn't mean that a heavier person can't ride in comfort, but it does mean that that rider has to be a little more careful what roads they take.
Just saying...
ponydrvr
Member
Absolutely correct - I did the full Gonzo mod. I'm ~270 lbs, I use 42 Liter side cases and a 52 Liter top case. I have also shortened the suspension connecting links raising the rear nearly 1 1/2 inches. Fully loaded the ride is perfect. Lightly loaded - it gets a little rigid at times. But, all things considered, I wouldn't even think of going back to the OEM setup or not trimming the rubber bumper. I have never seen a po-go style response from my suspension. I have thought hard about installing cartridge emulators up front but I'm not sure there is significant improvement to be made.
Michael Moore
Member
Your modification of the links may have moved you into a different area on the suspension curve/changed the wheel rate. You should not presume that spacer/preload mod alone (without the link modification) would give the exact result you have gotten.
I've ridden bikes with well-sorted Emulator installations and there are plenty of other people who've got them on NC/CTXs and other bikes and I can assure you that they will make a noticeable improvement over the stock Honda fork **if properly set up and with the correct springs for the normal load**. Damper rod forks are a poor design and they've been a poor design for 50ish years. But they sure are cheap to make!
The CTX is built to a fairly low price point and to hit that Honda went for suspension components that are "good enough for long enough" for whatever lightweight rider loading/not-very-demanding-use scenario they decided to use in specifying the order to Showa.
If you buy a lower-spec Hyundai you shouldn't expect it to ride like a Lexus. If you want the Lexus ride, you need to be prepared to spend more money, either buying a higher spec vehicle to start or buying aftermarket suspension upgrades.
cheers,
Michael
I've ridden bikes with well-sorted Emulator installations and there are plenty of other people who've got them on NC/CTXs and other bikes and I can assure you that they will make a noticeable improvement over the stock Honda fork **if properly set up and with the correct springs for the normal load**. Damper rod forks are a poor design and they've been a poor design for 50ish years. But they sure are cheap to make!
The CTX is built to a fairly low price point and to hit that Honda went for suspension components that are "good enough for long enough" for whatever lightweight rider loading/not-very-demanding-use scenario they decided to use in specifying the order to Showa.
If you buy a lower-spec Hyundai you shouldn't expect it to ride like a Lexus. If you want the Lexus ride, you need to be prepared to spend more money, either buying a higher spec vehicle to start or buying aftermarket suspension upgrades.
cheers,
Michael
ponydrvr
Member
I'm reminded of the saying -"You can put lipstick on a pig ....".
My CTX is definitely not a pig in my eyes and I thoroughly enjoy riding it. It just is not a high priority to me for it to be "Lexus" like in function. I'm to old to care about that, speed, options, and the like. Just need it to be suitable function for me.
Isn't that what mods are all about anyway?
Cheers,
Ralph
Michael Moore
Member
The CTX and NC use the same swing arm and links (and it appears the upper damper mounting position on the frame), the extra travel is gained in the damper. Both models have dampers with the same compressed length giving the same ground clearance at full bump -- the NC has a longer extended length with more shaft movement. If you got more movement from leveraging the CTX damper then you should have a lower wheel rate than stock. The spring would need to be stiffened by the square of the leverage ratio increase to maintain the original wheel rate. I don't know if Honda used the same wheel rate on both models or not. If they did, then your rear suspension should now be softer than an NC.
I hope you checked the full-bump position of the bike after the changes. Finding out that you lost ground clearance at that position (if you did) is best done in the garage, not in the middle of a corner.
FWIW, the standard spring that comes with the Ohlins HO 070 for the NC is shown as a 140 N/mm rate which is 800 lbf/inch. I looked in my notes and my Ohlins (supplied to the original owner by Cogent) has "the Ohlins code of 1095-64 / 160. According to the decoder chart, that means its a 160 N mm spring, or 16.3 kg mm. " That 913 lbf/inch. The prior owner also was about 215-220 lbf before adding all the riding gear and he said he was happy with that spring rate. I've yet to ride the bike with the Ohlins so I can't comment on how it feels.
cheers,
Michael
ponydrvr
Member
I'm not sure what you said means.
FWIW, I know this:
1. when I shortened the rear suspension links the unloaded rear of the bike was lifted by nearly 2 1/2 inches;
2. the bottom of the wheel was lowered by ~2" as supported by the center stand and connected to the suspension;
3. reducing the damper bumper thickness added to the available rear wheel movement and damper length of travel;
4. I added 4 ea,. 10 mm, flat steel washers to increase the preload and adjusted for a 1" sag when seated and with typical loaded cases.
I have no doubt that the rear damper will need to be upgraded at some point, just not yet. And, as I said previously, I have not bottomed out the rear suspension since the change. Bottoming out the rear was occurring with some bone jarring frequency prior to the change too. Finally, I was able to restore the ability to lean over in turns, at speed, even fully loaded. So much so that I seldom get over enough now to scrape the floor boards.
I am absolutely convinced that the PR4 tire are also a part of this solution. I installed a Pirrelli rear and immediately the handling and feel went to **** . I'm staying with Michelins.
I think I'm like the blind pig that found a nut. Just got lucky.
Cheers,
Ralph
FWIW, I know this:
1. when I shortened the rear suspension links the unloaded rear of the bike was lifted by nearly 2 1/2 inches;
2. the bottom of the wheel was lowered by ~2" as supported by the center stand and connected to the suspension;
3. reducing the damper bumper thickness added to the available rear wheel movement and damper length of travel;
4. I added 4 ea,. 10 mm, flat steel washers to increase the preload and adjusted for a 1" sag when seated and with typical loaded cases.
I have no doubt that the rear damper will need to be upgraded at some point, just not yet. And, as I said previously, I have not bottomed out the rear suspension since the change. Bottoming out the rear was occurring with some bone jarring frequency prior to the change too. Finally, I was able to restore the ability to lean over in turns, at speed, even fully loaded. So much so that I seldom get over enough now to scrape the floor boards.
I am absolutely convinced that the PR4 tire are also a part of this solution. I installed a Pirrelli rear and immediately the handling and feel went to **** . I'm staying with Michelins.
I think I'm like the blind pig that found a nut. Just got lucky.
Cheers,
Ralph
Michael Moore
Member
Ralph, let me recommend some reading that will make a lot of this suspension stuff make sense:
http://www.racetech.com/page/title/Suspension Bible
Note: A good friend of mine did all the graphics in the RT book. If you want a solid grounding in different types of dampers (front and rear) then it is hard to go wrong with a copy.
For a more detailed coverage of suspensions and many other chassis topics then there is Tony Foale's book (currently only available in PDF)
https://tonyfoale.com/
Note: Tony is a good friend of mine, but that doesn't stop him from being an internationally-known chassis guru. Tony's chassis software (and there is some small freeware programs he's written on his website) is a huge time saver over manual computations and very reasonably priced if you are into designing your own suspension/complete chassis.
http://www.broadlandleisure.com/
Note: I used to be the North American distributor for John Bradley's first two volumes (now out of print). But John mentioned to me that Volume 3 (chassis setup) is getting close to being done and when it is he'll put the first two volumes back into a final printing. Powell's Books in Portland OR should be the one distributing the new printing(s)
I generally had no problem selling both John's two volumes plus a copy of Tony's book to people and having them be quite happy to have all of them. I know that I'm happy to have them all.
Full bump = full compression, full droop = full extension.
Your shortening of the bump rubber will have added some shaft travel which then gives roughly 2.7X that increase in wheel travel (if everything else is kept unchanged). However, that 2.7X leveraging of the damper is not changed -- for every 1 unit of damper travel you'll get 2.7 units of rear wheel travel.
Changing the links can have several different effects. You might change the leverage ratio (either increasing or decreasing it) and you will also change the position of the wheel/swing arm at each end of the suspension travel. I think people who lower their NCs generally put in a longer link, if that is the case and you shortened the links then you will have raised the seat (dropped the wheel).
Linkage rear suspensions can be very touchy on the suspension curve response to changes in pivot locations. Sometimes just a few mm can make things very different, other times it may not make much of a change. The only way to be sure is to either calculate the changes (which can be done with Tony's software or by measuring the amount of wheel travel for each unit of damper travel).
You may have dropped the rear wheel when on the stand with the changes, but you also need to look at where the rear wheel is (vs the original location) when the suspension is fully compressed to get the full picture of what the modification did.
If your rear wheel travel is now greater than 2.7X the damper travel (from the link modification) then you've increased the leverage on the damper. That would mean that you've got an effectively softer wheel rate. Wheel rate is what you want to use to compare things, as you could have the same wheel rate from a spring/damper combo that is at a 1:1 leverage ratio (this is your standard dampers back above the rear axle so 1" of wheel motion is 1" of damper shaft movement) or a damper moved up 50% along the swing arm so you have 1/2 as much damper movement for the same wheel movement, but the spring rate needed for the same wheel rate will be 4X higher.
I hope that makes things a little clearer for you. The important thing is that whatever changes you make 1) are safe and 2) an improvement.
cheers,
Michael
http://www.racetech.com/page/title/Suspension Bible
Note: A good friend of mine did all the graphics in the RT book. If you want a solid grounding in different types of dampers (front and rear) then it is hard to go wrong with a copy.
For a more detailed coverage of suspensions and many other chassis topics then there is Tony Foale's book (currently only available in PDF)
https://tonyfoale.com/
Note: Tony is a good friend of mine, but that doesn't stop him from being an internationally-known chassis guru. Tony's chassis software (and there is some small freeware programs he's written on his website) is a huge time saver over manual computations and very reasonably priced if you are into designing your own suspension/complete chassis.
http://www.broadlandleisure.com/
Note: I used to be the North American distributor for John Bradley's first two volumes (now out of print). But John mentioned to me that Volume 3 (chassis setup) is getting close to being done and when it is he'll put the first two volumes back into a final printing. Powell's Books in Portland OR should be the one distributing the new printing(s)
I generally had no problem selling both John's two volumes plus a copy of Tony's book to people and having them be quite happy to have all of them. I know that I'm happy to have them all.
Full bump = full compression, full droop = full extension.
Your shortening of the bump rubber will have added some shaft travel which then gives roughly 2.7X that increase in wheel travel (if everything else is kept unchanged). However, that 2.7X leveraging of the damper is not changed -- for every 1 unit of damper travel you'll get 2.7 units of rear wheel travel.
Changing the links can have several different effects. You might change the leverage ratio (either increasing or decreasing it) and you will also change the position of the wheel/swing arm at each end of the suspension travel. I think people who lower their NCs generally put in a longer link, if that is the case and you shortened the links then you will have raised the seat (dropped the wheel).
Linkage rear suspensions can be very touchy on the suspension curve response to changes in pivot locations. Sometimes just a few mm can make things very different, other times it may not make much of a change. The only way to be sure is to either calculate the changes (which can be done with Tony's software or by measuring the amount of wheel travel for each unit of damper travel).
You may have dropped the rear wheel when on the stand with the changes, but you also need to look at where the rear wheel is (vs the original location) when the suspension is fully compressed to get the full picture of what the modification did.
If your rear wheel travel is now greater than 2.7X the damper travel (from the link modification) then you've increased the leverage on the damper. That would mean that you've got an effectively softer wheel rate. Wheel rate is what you want to use to compare things, as you could have the same wheel rate from a spring/damper combo that is at a 1:1 leverage ratio (this is your standard dampers back above the rear axle so 1" of wheel motion is 1" of damper shaft movement) or a damper moved up 50% along the swing arm so you have 1/2 as much damper movement for the same wheel movement, but the spring rate needed for the same wheel rate will be 4X higher.
I hope that makes things a little clearer for you. The important thing is that whatever changes you make 1) are safe and 2) an improvement.
cheers,
Michael
ponydrvr
Member
Thanks for the detailed explanation. You have helped clear up somethings for me.
I made these mods over 30,000 miles ago. I still have a lot (unmeasured but at least 3/4") of clearance on the tire top side when the damper is fully compressed.
You are correct in that the wheel to damper ratio has been changed and a higher spring rate is needed to balance the suspension. I just didn't know where to go to get a proper spring with out the damper. Being an old tight-wad I wasn't going to spend big bucks for a proper damper and spring when what I have is working ok. I know it could be better, but it works well enough for me.
I'm very close to being spring bound on full compression, but there is still some space left - just not much.
Thanks for the info Michael.
Cheers,
Ralph
I made these mods over 30,000 miles ago. I still have a lot (unmeasured but at least 3/4") of clearance on the tire top side when the damper is fully compressed.
You are correct in that the wheel to damper ratio has been changed and a higher spring rate is needed to balance the suspension. I just didn't know where to go to get a proper spring with out the damper. Being an old tight-wad I wasn't going to spend big bucks for a proper damper and spring when what I have is working ok. I know it could be better, but it works well enough for me.
I'm very close to being spring bound on full compression, but there is still some space left - just not much.
Thanks for the info Michael.
Cheers,
Ralph