'86 Xr/xl 600

[Bateman147]

Hi -

I've got both an XR and an XL 600, both '86s. The XR I got because it dropped a valve through the piston, and the XL needs bore/piston/rings (I also got it dirt cheap).

As near as I can tell it looks like I ought to be able to use the XL top end on the XR bottom end and get 628cc. Is there any hidden pitfalls in going this route? As near as I can tell the XR and XL cylinders are the same height, and it looks like everything should bolt right up and work.

Thanks!

Michael

 

[Senior KX Rider]

moved

 

[beer_stud_76]

bateman -

i'm no mechanic so i cannot say if your idea will work or not, but i'll run a few things i know about these two bikes past you and maybe it will tell you something that is not obvious to my mind.

1) the exhaust on the 650L is much more restricted in stock form than the 600R (i presume the air intake is more restricted as well.)

2) the carbs are quite a lot smaller on the 650L

3) the 650L has a heavier flywheel wieght (or maybe it just HAS one and the 600R does not, i cannot remember)

like i said, I have no idea if these things will have an affect on your plan. what i would do is give it a whirl. put the thing together and then have someone you don't particularly care for try it out for you.


jeremiah

 

[Farmer John]

XR/XL 600 Heads are the same in 86.
The only difference in the engines should be the stator, cam, & c/s sprocket.

I can't remember if honda put the smog holes in the 86 XL head or not. I know they are on the 87 XL head, but they could easily be pluged witha small plate & gasket.

 

[cujet]

If I remember correctly the XL had a shorter stroke and a 100mm bore. The head was supposed to be larger to fit the bore. There were big bore kits available for the XR that used a 100mm piston. HMMMMM.

Chris

 

[Bateman147]

Hi Guys -

Thanks for the advice. I was able to get a few more spare parts and came up with a complete engine. Farmer John is right - the XR and XL heads are identical. I didn't measure the cam as of the 5 cams I have only one is any good (from the XL originally).

I was able to build a good running engine with the XR bottom end, another XR cylinder and matched Arais higher comp. piston, the XL head/cam etc, and the XL left sidecover (for the alternator etc.). The engine is in the XL frame for right now, with the XL carbs and a Supertrapp exhaust.

I'll eventually send the XL cylinder out for a rebore, buy a good 10.5 or 11:1 piston kit for it and have one of the performance cams I've got repaired. The cylinder from the XL is identical except bore size, so I'll end up with a 100mm bore and 80mm stroke for 628cc.

At that point it'll probably go back in the XR frame and see high country duty, but for now I'm going to enjoy having a hooligan street bike. I may even move the XR suspension over to the XL if it looks like it'll all work. My regular dirt bike is a '96 Yamaha WR250 and for the riding I do (40-60 mile days at Belfair, WA) it's perfect. But when the guys go to the high country (or Baja) I'll want the XR I'm sure.

Again - thanks for the help.

Michael

 

[beer_stud_76]

you ride tahuya? i need someone to show me around there

 

[Highbeam]

For tahuya take a peak at the chapters:west chapters section of this forum. It seems someone is always planning a ride to tahuya.

I would say it is one thing to scrounge together parts for an old rat bike. But when you start buying parts and upgrading the old bike remeber that it is only worth a few hundred bucks. I bought my xr500r for 600 bucks.

What do you consider high country?

 

[Bateman147]

More XR/XL questions

Hi -

So I've got this '86 XR/XL hybrid going, with a good engine built from the good bits and pieces from both bikes and some other spare parts. I recently got the engine put together and it's running strong with no smoke or piston slap anymore. :-)

Since they changed the laws in Washington and I can't get the XR frame street licensed I'm working on making the XL into as much XR as possible. I've already got a dedicated dirt bike, and I want this one to have a license plate on it.

It looks to me like I should be able to move the XR front suspension right over to the XL as long as I move the triple clamps and everything. I'll likely have some issues with instrument cluster/key switch mounting, but that doesn't seem insurmountable.

Do any of you guys know if the rear suspensions are interchangeable? The XR swingarm looks to be about 2" longer, and the suspension has longer travel but it looks to me like it ought to bolt right in. And it looks like if I switch the kickstands (XR is longer) it all ought to work.

Have any of you guys tried this? I realize it'll be a mongrel but it'll be as close as I can easily get to a streetable XR, built from pieces I already have in the shop.

Michael

 

[Bateman147]

Most all of the parts I already have - I'm into both donor bikes less than 500 bucks. If I decide I need more power (the bigger piston for the XL jug) I'll only be out a couple hundred more, and at that point the engine will be in rather good shape, and rather strong. I'm a roadracer with an almost full shop so the mechanical work is no big deal, but the budget for dirt stuff is almost nil as it all goes into the roadrace program.

I figure what the heck - I might as well make the XL the best I can. It's a fun project. I realized last night that I can't get the XR frame titled for street running in Washington, so I guess I'll be concentrating on moving as much of the XR gear (suspension, etc) to the XL chassis as I can. It'll end up a but heavy but will have a plate too.

By High Country I mean the Cascades. I dirt ride with a bunch of retired and current roadracers. They ride the cascades in the summer, but I don't end up going as I spend the summers mostly roadracing. I'm hoping to be able to go with them one of these days though between seasons (after roadrace season and before the cascades are closed down due to snow).

Michael

 

[Bateman147]

More XR/XL questions

Hi all -

I've got two bikes from '86, one an XR600 and one an XL 600. They both had shot motors, but I've managed to build a good motor from the remains of both and some other spares. I'm looking to have a streetable thumper, and in Washington you can't license XR frames anymore, so I'm stuck with the XL frame.

Have any of you moved the suspension from an XR frame to an XL frame? I haven't measured anything yet, but it looks like the suspension should bolt right up on both ends. I'll have a bit of an issue mounting the key switch/headlight on the XR triple clamps probably (no big deal).

The XR rear suspension has more travel and a longer swingarm, but the mount points look just about the same and the kickstand mount is in about the same location (XR has a longer kickstand) so it looks like the rear suspension should bolt up as well. (I hope).

Anyone have any experience with that?

Michael

 

[Bateman147]

Shoot guys - sorry. I thought I was starting a new thread and couldn't figure out why my message wasn't showing up. The answer is that it was showing up here - three times. Doh! Call me a goober.

Michael

 

[PeteN]

Batemen, you're a goober! But I think I've called you that before. You should call Tyler, he did almost the exact same thing about 10 years ago. About the XL top end on the XR bottom, it might work, but you had better check the piston height. The piston may protrude above the deck due to different rod length/stroke/piston height. FYI By the way, you better come out and race Supermoto (superTT) with that thing!!

 

[Bateman147]

Heh. Hi Pete. Thanks - I'd forgotten that Tyler was an XR/XL sicko. Apparently the cases make up the difference between the two rod lengths - the cylinders are exactly the same height. I've got the engine all put together and running - but with an XR cylinder/piston. Once I get a job again I'll have the XL cylinder bored and have one of the dead cams I have repaired/reground with more duration. For now it's running strong with the XR high comp. piston and XL head. Anyone know if the XR and XL cams were different in '86?

I put the XR rear suspension on it last night and it fit up mostly fine. I had to use the XL linkage and do some clearancing work, but for the most part it was a bolt-up swap. 3" more ride height with a corresponding increase in suspension travel, plus a better and adjustable shock. Not bad. It looks like the front suspension will slot right on too, but I'll have to do some work to the upper triple to make mounts for the instrument cluster/headlight mounts and keyswitch.

I've thought of SuperTT with it - I might as well come out and get my butt kicked on an old heavy junker eh?

Michael