XL600R mods

Hi, I was amazed i had no replies on my last post so i'm gonna try again, someone must have some input on this.

I'm doing some rejigging on one of my XL600R's to improve it for road use only and wondered if anyone has been here before, i did search the forums but haven't found precise answers.

I've stripped the bike right down to the frame and i'm having it powder coated, i'm then going to fit a late XR400 rear shock with Xr600 (1999 model) forks with progressive springs, leave the airbox off completely and fit 2 50mm cone air filters. I'm thinking of chopping a few inches from the back of the frame to shorten it slightly and leave the carring rack off then fitting new rear mudguard (KTM style). I know i'm probably looking at the need to re-jet the carbs, so i'll replace the exhaust while i'm rebuilding, probably a FMF unit but was wondering if there was a shorter alternative on the market??

Has anyone done any of these before and did they work/not work?

Thanks for any input on this.

I'm restoring an 83 XL600R right now too.

But I always keep them 100% original for resale.

So I'm not much help to you on the mods.

I'll post some pics when I'm done with it.

I did go with a smaller rear 41 tooth sprocket an jet hot coated exhaust with bigger jetting.

65 for the slow jet an 122 mains in each carb.

That's it for my mods.

I also put some 70% street/30% dirt tires on it for better street manners.

You might want to check your cam an rockers, these bikes seem to eat them.

Hi, thanks, i think the engine is OK, it was it's only saving grace when i bought it as i bought it on ebay and collected it in the dark and didn't realise how tatty it was, knackard chain and sprockets, warped rear drum, not great, the only good thing was that it's had an engine rebuild and a big bore kit used, the difference between this XL and my other is really noticable power wise, at £800 i paid way too much for it, oh well, live and learn.

Supertrapp still sells a 4" disk exhaust for the XL600R. I just saw a couple of places offering new ones. I have a battered 4" disk Supertrapp that I test fitted to my XL600R and it is definitely shorter than my bazooka style FMF Ti4 system.

But I will probably end up with a FMF Q2 on my FMF high flow stainless steel header. The 14" Ti4 is way too loud and the longer Ti4's cost more than the Q2 by the time you add the insert and spark arrestor. But I like leaving 10 pounds or so in garage. And the stainless steel header is way lighter than stock and looks great. So I am definitely going to stay with a FMF system. So far the Q2 looks like the best bet for keeping the sound AMA legal.

Jet kits are also still available since I bought and installed one in my bike last year. Kits are nice since they give you several options. Another upgrade that shaves a little tonnage off the pig is a Clarke plastic tank. Those are definitely still available since I just got one last week. And, typical of Clarke tanks, it is a perfect fit. I think it looks great in see through natural. And if it is like my last Clarke, it will outlive the bike and possibly me.

Unless you really need the cush hub, an XR600 aluminum swingarm and rear wheel make a nice upgrade that looks good and leaves a yet more tonnage in the garage. You have to replace the swingarm, linkage and wheel as a unit though. The cush hub XL600 wheel will not fit an XR600 aluminum swingarm and the linkages do not interchange.

Cheers matey, i've not got round to the exhaust yet, i might get one made, slightly shorter than normal, there seems to be a lack of options here in the UK.

Looking through the posts i've found the most mind bendingly complex subject, forget astro-physics, try the subject of XL600R carb re-jetting, i'm so confused, what size jets on what year carbs???????? Arrrrrrgggghhh, oh sod it, i'll leave them as they are, if it burns out the valves then so be it.

I should get the frame, swingarm, tank and bash plate back from the powder coaters tomorrow, i'll start rebuilding the bike at the weekend.

Supertrapp still sells a 4" disk exhaust for the XL600R. I just saw a couple of places offering new ones. I have a battered 4" disk Supertrapp that I test fitted to my XL600R and it is definitely shorter than my bazooka style FMF Ti4 system.

But I will probably end up with a FMF Q2 on my FMF high flow stainless steel header. The 14" Ti4 is way too loud and the longer Ti4's cost more than the Q2 by the time you add the insert and spark arrestor. But I like leaving 10 pounds or so in garage. And the stainless steel header is way lighter than stock and looks great. So I am definitely going to stay with a FMF system. So far the Q2 looks like the best bet for keeping the sound AMA legal.

Jet kits are also still available since I bought and installed one in my bike last year. Kits are nice since they give you several options. Another upgrade that shaves a little tonnage off the pig is a Clarke plastic tank. Those are definitely still available since I just got one last week. And, typical of Clarke tanks, it is a perfect fit. I think it looks great in see through natural. And if it is like my last Clarke, it will outlive the bike and possibly me.

Unless you really need the cush hub, an XR600 aluminum swingarm and rear wheel make a nice upgrade that looks good and leaves a yet more tonnage in the garage. You have to replace the swingarm, linkage and wheel as a unit though. The cush hub XL600 wheel will not fit an XR600 aluminum swingarm and the linkages do not interchange.

Hello Grreatdog, please excuse the intrusion but this is my 1st time back on the forum since '06. I have an '87 XL600R so I noted your cleverly conceived mods for future ref & thanks. The OEM owners' manual says to adj the chain with the rear wheel off the ground. I'm looking around for a swingarm stand to simplify this job and am wondering which stand is compatible with the XL600. Any XL600R owners out there already have one that works well with this bike? Thanks in advance for your valuable input.

You might want to check your cam an rockers, these bikes seem to eat them.

pwrpapa, I've heard the same thing about cams & rockers, but, luckily I haven't had that experience w/ my bike yet & it has 18K miles on it. Since I've used Schaeffer 'moly' oil for the last 9K, that alone may have saved my cam lobes 'moly' has a VERY low friction coefficient. However, I had to replace my alternator stator about 500 miles ago & I don't know if the moly oil had anything to do with that. Maybe some of the other XL600R owners have had to replace their alt. stators at similar mileages while using NON-MOLY oils. If so, I'd like to hear from them so I would know whether or not to suspect the 'moly' in the Schaeffer oil for shorting out my stator.

Again, thanks for any valuable input on this subject.

I drilled out (to 1/8" if I remember right) the banjo bolts holding the oil pipe/tube/line to head and crankcase.

The upper banjo bolt seemed to be more restrictive. than the actual pipe

Some have replaced the entire line with bigger hose but that was to complicated for me.

One thing I like about the cush rear wheel is it saves on the tranny.

Has anyone removed the airbox and tried cone filters?

Or fitted an XR rear shock?

Or fitted an XR rear shock?

I was asking about mods for the XL over in the XR600/650 forum a few weeks ago. It appears that the early XR600 shocks will fit and give more travel. Same for a front end from a XR600.

Mine has a Works Performance XR600 shock so I would have to say that an XR600 shock works. As for XR600 forks, even if they didn't fit an XL600 the worst outcome would be having to get XR600 triple clamps. After '96 XR600's went to an excellent cartridge fork. That would be a nice upgrade. But I don't think I would sweat the change for earlier years. I just don't think you would gain that much.

Mine has a Works Performance XR600 shock so I would have to say that an XR600 shock works. As for XR600 forks, even if they didn't fit an XL600 the worst outcome would be having to get XR600 triple clamps. After '96 XR600's went to an excellent cartridge fork. That would be a nice upgrade. But I don't think I would sweat the change for earlier years. I just don't think you would gain that much.

Hi, yes, i've managed to get a set of 1999 XR forks and have got some progressive springs for them, they should work nice. I've also got an XR rear shock but it has the canister fixed on the side (not on the tube) and this will get in the way of the airbox connector to the carb, i was wondering about re-routing one side or bolting on some sort of airfilter setup straight onto the carbs, like cone filters.

I've just got the frame/tank/swingarm and bash plate back from the powder coaters, they look awesome.

My Works shock has a remote reservoir so I lucked out there. Some K&N filters would be nice on a street machine. But they are limiting if your offroading involves water crossings. If you plan on keeping it trail ready, why not keep your eyes on eBay for an XR600 airbox and filter?

You would lose the battery box, but so what? You don't need a big battery on an XL600R anyway. I already ditched the metal contraption that holds the battery on mine because I run a small sealed battery up under the seat. Nothing in the battery hole except wiring these days.

I think you would also have to use an XR600 left side panel if you swap out the airbox. I am pretty certain it is different.

I was going to keep this one for road use only as i have another xl600r that i will use off-road so i could change the air filters for cone ones if they will work, i was wondering about backfire into something so close to the inlet, i'll have to put tags on the filters with my name and address on them as i recon they'll end up being fired off into another county.

The rear shock will be fine if the cone filters workout ok, i've managed to get the stage 2 jet kit for the carbs, i'm surprised nobody has been down this route before as i can't find any posts on any site for it, this makes me wonder if i'm doing the right thing or not.

I used XR400 forks on my XL600 with .46kg springs and compression stack mods. They work good for me. After some experementation and trial and error I settled on an 86 XR600 rear shock with remote reservour that allowed stock air filter usage. I put on a 11.5kg rear spring and 180psi nitrogen charge. It works way better than stock. My personal experience has proven to me at least, the the best suspension tuning you can do is spring rates matched to weight and proper sag settings. My bike actually rides plusher with much heavier springs than before because it is running now in the plusher range of the shock instead of the heavily dampened end of travel.

What did you use for a sealed battery? I want to get rid of the acid problem and maybe an ounce of two of weight.

I'm restoring an 83 XL600R right now too.

But I always keep them 100% original for resale.

So I'm not much help to you on the mods.

I'll post some pics when I'm done with it.

I did go with a smaller rear 41 tooth sprocket an jet hot coated exhaust with bigger jetting.

65 for the slow jet an 122 mains in each carb.

That's it for my mods.

I also put some 70% street/30% dirt tires on it for better street manners.

Pwrpapa,

I'm with you keeping my 18K '87 XL600R original (except for a Lockhart oil cooler I've added) and I'll soon add a Scott Oiler, too if it will feed the SAE 80W90 transmission oil that Honda recommends for the chain. I'm running a 15T countershaft with a 43T rear sprocket. If you are running a 15T countershaft with your 41T rear, I probably can, too. Are you running a 15T countershaft sprocket?

I searched the world over and found a 16T front sprocket that I use with the stock 43 rear. The advantage there is that I am able to run as small as a 13T front sprocket for trail and 16T for road with the same chain length. On steep grades with 16T I have to downshift into fourth, but it is comfy on the flats for sure. 4200 RPM at 65MPH. I also plan to install an oil cooler. I have one from a XR400 that looks doable.

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