Topic: Frontend Fork Swap Worth It/Alternatives

[zeech]

I ride in LA sometimes up to 70 miles a day and these freeways can really take a toll on you bouncing around all day. I'm not sure if I have stock or progressive front springs due to the PO. I recently replaced my fork oil to level and it rides about the same.

I know you can do a frontend swap which would probably make the bike feel far more smooth and ridable, but I'm wondering if there are any alternatives that might be cheaper? I could try a new pair of progressive fronts I suppose.

Curious to what others have done and seen good results with. Thanks!

[calj737]

Progressive Springs or Cartridge Emulators are generally the "upgrades" for stock forks. Swaps, generally are to improve sport handling.

Another thought, change your tires. Good, modern Avons (one brand as an example) offer better sidewall construction and can improve your comfort. You don't state the condition of your bike, tires, seat, etc, so it's hard to give you relevant advice.

You'll get tons of ideas and input, but do yourself a favor, and indicate what you have, and what budget you may have. This elicits the best advice.

[zeech]

Condition of bike is great, cafe style, fresh engine. Running clip ons, Dunlop K70s, seat is a cafe style that's plenty comfortable, stock style rear springs.

I'm looking for front end stiffening or something to limit the amount of shock transmitted from the ground to my body. I have a CL350 that feels like it has stiffer frontend and eats up the washboard freeway effect and sudden bumps a lot better than my 550 does. It's very mushy feeling, soft but also allows too much road transfer.

[Trad]

Condition of bike is great, cafe style, fresh engine. Running clip ons, Dunlop K70s, seat is a cafe style that's plenty comfortable, stock style rear springs.

I'm looking for front end stiffening or something to limit the amount of shock transmitted from the ground to my body. I have a CL350 that feels like it has stiffer frontend and eats up the washboard freeway effect and sudden bumps a lot better than my 550 does. It's very mushy feeling, soft but also allows too much road transfer.

It sounds to me like the springs may be pretty well worn. I would say throw in some progressive springs and that should help things.

You could also make some spacers out of PVC pipe and insert them on top of the spring then assemble the compression nuts. This puts more load on the springs resulting is a stiffer fork.

[seanbarney41]

I would replace those rear stockers first.  They are mush central on the 550, and many other 1970's Jap bikes for that matter.

[Bailgang]

I put new progressive springs in the front forks of my 75 550 and it did definitely stiffen it up, what it did more than anything though was expose how shot the rear shocks were which were pretty much pogo sticks. I sold the bike before I ever got around to installing new rear shocks.

[martin99]

+1 on tires. I'm not a fan of K70s. The one on the back of my Norton was, oddly, better in the wet than on a dry road, often throwing the back out on bends, which is why I changed it. An unexpected bonus was a noticeably less bumpy ride.

[zeech]

Going to go with new front and rear shocks and see what that does to start. Most people dislike the K70s but I like them, have to tell if they are actually a part of the cause or not. I do like a more vintage style tire, looking at the Firestone ANS which seem to be pretty popular.

[calj737]

Z - not to go too far on you but, you do realize every modification you are making is actually increasing the felt vibration, right?

I'm all for an aesthetic, ie vintage tires. But they aren't as generous with absorbing bumps. While your cafe seat may be pretty comfy, if it's hard mounted to the hoop, guess what? More vibration. And lastly, clip-ons. For rider comfort, they are the worst.

Don't get me wrong- I dig cafe bikes. I have clip-ons on my bikes. BUT, for traffic commuting on long bumpy roads, a sport bike bar, a naked bar will be much more comfortable and compassionate.

Just understand these aspects so that you decide if the money you spend is actually addressing the problem. From the list suggested, I see it very clearly getting worse, not better.

[zeech]

None taken calj737 — Though I'm not looking to reduce vibration at all, never said that was my problem, the issue I have is the front end is very mushy and every washboard concrete casting on the freeways goes right into me and just shakes you up and down. Yes clip ons increase this. Bumps rock the whole bike. There is little to no actual vibration issues that i have. Tires not absorbing enough of the bumps makes sense, but all those other things are not my complaint. I don't know how it can get worst by replacing worn shocks.

And again, my 350 feels much more solid and it has a nearly identical setup except I have flat  bars, but I can tell the shocks are actually eating up the bumps where they are not on the 550.

If the tires are the only thing causing my issues, I'll give away my three bikes.

[calj737]

My comments about vibration were in response to your description of "bouncing around all day". Many feel that stiffer suspensions (and I am one of them) actually shorten the bumps you feel. Yup, you still hit them, but the dissipate far more quickly. It's a preference difference really.

If your rear shock are worn, they should be replaced. Regarding Prog Springs, you can install spacers as suggested to see fit hat helps before spending the money. I will say this, a 550 is not going to handle the same as a 350. Lighter bikes, different CG. 

But getting the weight of your wrists helps your torso ride the bumps instead of fighting it with your hands. Post your results so we can all learn from your outcomes.

[zeech]

Roger that. I would love to have a stiffer, shorter felt bump. I get frontend dive from just sitting on the bike they are so soft. I'll see what happens with the spring replacement and report back.

[Ricky_Racer]

Hi, Zeech. Suspension setup can be a little complex so you might want to do some research in the sportbike world. Here's a start: http://www.motorcyclistonline.com/howto/122_0508_motorcycle_suspension_setup/.

IMHO, yes do fit a quality set of rear shocks; that'll take care of the rear end assuming that your swingarm bushings are in good shape.

Then, consider your front forks: if you have that much static sag as you've indicated, you might want to head over to your nearest LA shop that does race bike suspension work and have them check and adjust (spacers) your sag. Once that is accomplished, you can address how the bike responds at speed by changing springs (Race-tech IIRC only does straight wound, Progressive does progressive), possibly installing cartridge emulators and then playing with the weight of your fork oil. Then, of course, you get to check your sag again! Pretty soon you'll be grinding off the dyna cover!   

BTW, I don't wanna start a "tire war" but you might want to consider a set of Bridgestone BT45 Battleaxes. They wear well and work in the twisties! RR

[RAFster122s]

550 and 500 are known for springs that wear out way too quick. So, as has been suggested. Replace springs, preload them to make them work and then tailor the shock oil to suit the stiffness you want or need to get the bike to handle better. I prefer the bike to be a little stiffer and able to dampen the up and down. I tend to run heavier shock oil because I am larger than the "average bear" as well.  Works for me.

Modern fork on the bike gives you the ability to have a fork design that dampens better as well as provides capability to have modern high performance brakes.
That's my take on it.

[zeech]

Helpful info Ricky and RAF thank you!

[Duke McDukiedook]

IMHO, yes do fit a quality set of rear shocks; that'll take care of the rear end assuming that your swingarm bushings are in good shape.

^^ Rebuild your swingarm bushings before putting on new shocks, you would be amazed at the difference it makes. I had Mark (Hondaman) rebuild mine with bronze oillite bushings. You might want to look at a 75-77 Goldwang front end swap if you want a more robust front shock.

[bjbuchanan]

From the way you are describing what you want out of the front fork you are describing a cartridge style fork. That quick reaction and dampening without the jarring of damper rod style forks.

Look up the emulator threads, they are chock full of answers for literally everything you have said so far. You can do Mikesxs or RT but either way you gotta do a little tweak to the existing damper rods so they function properly. It is all detailed well in the threads, the left google search button.

In the mean time put a preload spacer in there to stiffen them up and play with fork oil weights

[zeech]

Quick update: Replaced rear shocks last night and that did give maybe a 10% improvement, so that's a nice start. Not an amazing change but I can definitely feel it's better. Will keep going.

Dukie: Yes, been thinking I need to do this as well, looking to pick up a set soon, thanks!

bjbuchanan: That sounds about right, I'll search around and see what I can find. Have definitely heard of them before.

[Bankerdanny]

I'll add my own + to the tire suggestion.

My Enfield had Asian K70 style tires on it and I switched over to Avon Roadriders and it was like I had a whole new suspension. Handling was dramatically improved by the more rounded profile, which helped the bike get into its lean faster, but the general compliance was improved to, leading to a much more comfortable ride.

The vintage look of the K70's is certainly a plus, but in the end, for me the far superior function more than made up for the loss of the classic form.