Front fork upgrade??

[impalablue]

Hi All,

I may be getting myself into trouble by lodging a complaint about the legendary XS11, but here goes!

I just picked up a beautiful 81 XS11 Special with 4-1 Jardine headers, and just like the 79 XS standard I had 20 years ago, it is incredibly fast and smooth, and I love that. What I don't love is the front suspension. My everyday bike (as in, the one set up with faring and saddlebags that I ride to work) is a Moto Guzzi California, and it is a surefooted, wonderful-handling machine that owes a lot of its stability and handling characteristics to the massive and well-damped front forks, along with some wonderfully wide (32") handlebars.

In comparison, the XS forks are spongy and don't do justice to that rockin' and rollin' powerplant. So far all I've done is to play around with the preload (airpressure) and switch to 15W oil versus the 10W. Not much satisfaction from that.

So--any ideas? Are there any known mods that can increase performance, or are there any high-performance replacement fork tube setups out there?

[bikerphil]

Couple of guys on here run FJ forks and trees, also seen a 'Busa front end fit on. Check on the UK site also, them fellas do some funky mods.

[TopCatGr58]

Aside from very $$ front fork assembly changes, you should look into installing a set of Progressive Fork Springs for the front, along with a TKAT fork brace. Might also look into replacing the rear shocks to cut down on the bucking bronco type ride from the jack shaft effect of the rear end.

With the progressive springs, most folks have found they don't even need any air in the tubes. 15w oil might actually make the front too stiff, you want/need some fork movement to smooth out the bumps and maintain stability. May have to experiment with the new springs and thinner oils??
T.C.

[MrFreeze5]

I am in the process of installing a 06 R1 front end on my XS11 project. My plan is to have a custom lower triple tree machined to accept the R1 forks and XS steering stem. This is the same thing I did for my FZR project and it was a very reasonable cost. Considering the total cost of the complete front end and custom triple, Im looking at about $600 total. I also saw a recent posting on customfighters.com by a board member on here, xschop, who custom grinds steering head bearings for the busa/gsxr front end swap. That is probably the easiest and cheapest method. Speaking of FZRs, I have seen the occasional XS11 with FZR forks, but after owning a FZR, I would have to strongly recommend against this. Theyre soft and spongy on a FZR, which is significantly lighter, and theyre not adjustable. FZ forks would be in the same boat, but have smaller brakes.

[dontlikeoc]

I apologize for side-tracking the subject but

-Is the handling of the stock Special forks that bad in general? How many people actually left the stock forks alone. I have one I am working on and general impressions will help.

- I am new to the 80's bikes...I dont even know how to adjust the air pumping. (I remember deciding not to use the air adjust at all on my 1984 GL1200 once.) Do you use a hand pump and a tire air pressure gauge? What is the standard psi to use? ( I could not find it mentioned in the shop manual I have in PDF...).

- I see more than a few Standards fitted with Special ends. Is that for air adjustment capability? Doesnt that make the rake/trail iffy?

[TopCatGr58]

Hey Don't Like OC,

IF you'll follow this link in the LINKS section

you'll find a PDF formatted Owner's Manual for the 81H/SH that'll provide those type of details....IIRC, it's not much more than 14 psi or so, yes, and hand pump is suggested to prevent blowing out the fork seals!

The XS11 has slightly wimpy upper fork tubes for it's size, and the specials are a little longer due to the leading axle design vs. the bottom of the slider design of the standards. This allows for some flexing, and so a Fork Brace is a definite handling improvement MOD. In later years on the 82XJ Yamaha included a bit of a built in FB in with the fender inner struts/mounts.

The bike has been described as having a hinge in the frame, mostly due to it's high powered engine. There's an article in the articles section about handling mods folks can do to help stiffen things up!

T.C.

[dontlikeoc]

Hi TC,

Thank you so much for the SH manual. Many things make a lot more sense to me now. (The one I bought off ebay was for Standard).

[yamahansolo]

has anyone tried the cartridge emulators? i have read about the mfor other bikes and they seem to be great...???

[motoman]

Mine is now 28yrs. old, factory full dress with CD in stereo housing. Finially had a seal leaking and remove forks and had them completely rebuilt with OEM seals. Stock original springs still in spec, used Silcolene 15w with 7psi of air on top. Works perfect with TKats fork brace removing the "hinge" effect. Rear is still stock KYB's with 5position spring load and 5position dampening. Works fine with adjustment on both set so bike compresses evenly front and rear. Problem with rear shocks is they do NOT have dampening on compression, just re-bound. Hitting my boot heel and couple times of bike parts hitting in twisties and bike tracking perfectly, considering its era, that's good enough for me. Oh, did I say I also ride a Honda ST...........go figure. In stock form if set up correctly, the XS handles fairly well, everything considered. The Specials handle twisties a bit better(loose the buckhorn bars) with the leading front axle. Yea, I know, angles, rake, etc. work out to be the same between the two set-ups. The handleing benifit some forget to consider is the weight transfer location and direction of gravity forces created on the leading front axle set-up is totally different and creates more weight on what is rolling on the ground......benifit being straighter tracking in front, among other factors present loading front end in corners. Anyway, you got the idea.

[jetmechmarty]

emulators

Not cheap, but I have been told by some I trust that the cartridge emulator is the hot ticket for the vintage bike.
http://old.racetech.com/evalving/eng...ngname=english

That should be coupled with straight rate springs based on the weight of the motorcycle and rider.

http://www.traxxion.com/

[impalablue]

Better is always....better

I am in the process of installing a 06 R1 front end on my XS11 project. My plan is to have a custom lower triple tree machined to accept the R1 forks and XS steering stem. This is the same thing I did for my FZR project and it was a very reasonable cost. Considering the total cost of the complete front end and custom triple, Im looking at about $600 total. I also saw a recent posting on customfighters.com by a board member on here, xschop, who custom grinds steering head bearings for the busa/gsxr front end swap. That is probably the easiest and cheapest method. Speaking of FZRs, I have seen the occasional XS11 with FZR forks, but after owning a FZR, I would have to strongly recommend against this. Theyre soft and spongy on a FZR, which is significantly lighter, and theyre not adjustable. FZ forks would be in the same boat, but have smaller brakes.

Hey, I salute your efforts to build a more perfect machine. No matter the love everyone had for the XS11, the fact is that it is not what it could be in all respects. I very much want to know how you like your bike after you do this. I might do it, too.

[impalablue]

"Buckhorn" special bars

Mine is now 28yrs. old, factory full dress with CD in stereo housing. Finially had a seal leaking and remove forks and had them completely rebuilt with OEM seals. Stock original springs still in spec, used Silcolene 15w with 7psi of air on top. Works perfect with TKats fork brace removing the "hinge" effect. Rear is still stock KYB's with 5position spring load and 5position dampening. Works fine with adjustment on both set so bike compresses evenly front and rear. Problem with rear shocks is they do NOT have dampening on compression, just re-bound. Hitting my boot heel and couple times of bike parts hitting in twisties and bike tracking perfectly, considering its era, that's good enough for me. Oh, did I say I also ride a Honda ST...........go figure. In stock form if set up correctly, the XS handles fairly well, everything considered. The Specials handle twisties a bit better(loose the buckhorn bars) with the leading front axle. Yea, I know, angles, rake, etc. work out to be the same between the two set-ups. The handleing benifit some forget to consider is the weight transfer location and direction of gravity forces created on the leading front axle set-up is totally different and creates more weight on what is rolling on the ground......benifit being straighter tracking in front, among other factors present loading front end in corners. Anyway, you got the idea.

OK, the OTHER thing that bugs me about the Special is those squinchy handlebars. Would appreciate a recommendation on the dimensions of something that worked for you. Noticed that one of the reviews of the Special posted on the site specifically mentioned these handlebars (in a negative way).

They are pretty cool looking, though.

[impalablue]

I apologize for side-tracking the subject but

-Is the handling of the stock Special forks that bad in general? How many people actually left the stock forks alone. I have one I am working on and general impressions will help.

- I am new to the 80's bikes...I dont even know how to adjust the air pumping. (I remember deciding not to use the air adjust at all on my 1984 GL1200 once.) Do you use a hand pump and a tire air pressure gauge? What is the standard psi to use? ( I could not find it mentioned in the shop manual I have in PDF...).

- I see more than a few Standards fitted with Special ends. Is that for air adjustment capability? Doesnt that make the rake/trail iffy?

Hey, I can't claim to know everything about this but when you are adding air make sure you don't get crazy and blast a bunch in there with a 120 psi compressor tank. There's not a big reservoir and I think you could blow out seals pretty easily...I actually use my pump for the shocks on my mountain bike.

You'll find that if you overdo the preload (in this case, the air pressure), that the forks will rebound all the way (with a klunk) after bumps.

[MrFreeze5]

Hey, I salute your efforts to build a more perfect machine. No matter the love everyone had for the XS11, the fact is that it is not what it could be in all respects. I very much want to know how you like your bike after you do this. I might do it, too.

Ill be sure to start a build thread once more of my parts come in and I can really get started. I love pics and documenting by builds. Hell, my FZR build is the largest thread in history on the FZR site

[impalablue]

Ill be sure to start a build thread once more of my parts come in and I can really get started. I love pics and documenting by builds. Hell, my FZR build is the largest thread in history on the FZR site

At least you are talking about switching Yamaha parts for Yamaha parts. I'm thinking (gasp) about cutting the front end off a Guzzi and welding it to the XS. Hopefully I can figure out something less extreme.

This is at least as sacreligious as a buddy of mine that dragged parts and pieces of two 1946 Chevy pickups out of the local scrapyard (both of them in about a gazillion pieces), put together into something resembing a single truck, figuring out a way to put the running gear out of 76 Chevy's underneath, and then putting in a Dodge 360....man, you should have heard the screams from the Chevy guys.