BHB's First XR600R + Winter Rebuild

[Brauhausbier]

I've been without a thumper for the past couple of years after owning a 2001 KLR and an 04' DRZ-S (should have kept the DRZ, it was sweet). I've just been riding my KTM950 for the past couple of years...but how I miss riding on trails of Eastern Oregon on a Thumper with the Bend Dual Sport Guys over there http://www.benddualsport.com/

Our resident "bike flipper" Wb-PDX here in Portland put up an 94' XR600R that he had found, got running, and flipped after owning two months just before the holidays. I happened to see it on our PNW Flea Market and just had a gut feeling about this XR and that WB-PDX was selling it...and the price was right: $1500.



This 94' XR has some good parts, and looks in pretty good shape. However it's very dirty, needs all new plastics, tires, sprockets, etc..so I'm electing to do a winter rebuild and get this XR ready for this next summer and do much of the labor myself. I want to thank Blakebird for his highly influential XR600 build thread and to Xrider and Mcma111 for all the sage advice about these venerable thumpers.

I just picked up this XR600 just before the holidays and finally had a free day today to start taking apart the XR and seeing just what I was in for. This bike is super dirty, and it's going to take some effort to bring a shine back to this XR. It's going to take some serious elbow grease.

Ready to Dive in!


Stripping the rear fender and accessories





The header is crispy


Making progress


Will be sending the stator off to BD for a rewind


This XR has a Mikuni Flat Slide Carb which runs ok, but I luckily have the OEM Keihin that I plan to re-jet and use.


Anyone know how to remove the throttle cable from the Mikuni Slider?? I've never seen this type of design.


Made a lot of progress today considering it was only about 35F outside. But it was very dry and sunny for January in Oregon.





I'm developing a long list for new parts and plan to take both the engine and suspension out to professionals for some TLC that this 16 year old XR could really use. I hope to get some time after work this week to finish taking apart the bike and then prepping and re-painting the frame.

Long Live XR's!!!

[switch]

Originally Posted by Brauhausbier

This XR has a Mikuni Flat Slide Carb which runs ok, but I luckily have the OEM Keihin that I plan to re-jet and use.


I'm developing a long list for new parts and plan to take both the engine and suspension out to professionals for some TLC that this 16 year old XR could really use. I hope to get some time after work this week to finish taking apart the bike and then prepping and re-painting the frame.

Long Live XR's!!!

Cheer mate. One question for ya: what's with the Mikuni carb? You're saying you're replacing it? Why? AFAIK it was supposed to be an upgrade to the stock one.

If you plan on improving in addition to restoring, you might want to check on GSMark's Oil Cooler thread. He's making XR 600/XL650/NX650 oil cooler kits! From what I've seen the stuff is as good as any OEM or aftermaket part, if not better.

[Blakebird]

That looks like a good bike to start off with, it's seen a few muddy days but appears to be in pretty good shape.
I kept my white tank looking good with a Scotchbrite pad and a spritz of WD40

"only 35 outside" ? That would be a heat wave here the last couple weeks.



He raises a good question. Did you ride the bike much before tearing into it? If so, was there an issue with throttle response or something? Most people don't like the Keihin's "sticky slide" feeling off idle - you'll probably have people lining up to take that Mikuni off your hands

Originally Posted by switch

Cheer mate. One question for ya: what's with the Mikuni carb? You're saying you're replacing it? Why? AFAIK it was supposed to be an upgrade to the stock one.

[switch]

Originally Posted by Blakebird

He raises a good question. Did you ride the bike much before tearing into it? If so, was there an issue with throttle response or something? Most people don't like the Keihin's "sticky slide" feeling off idle - you'll probably have people lining up to take that Mikuni off your hands

That was implied behind the question. My NX could use a better carb :P

[brad21]

Big thumpers rule.

[Easy-Z]

Nice going Eric! Tearing it down is the easy part. DAMHIK.

[sector]

Wow! Looks like quite a project! I hope you remember where every part goes! Have fun. That bike looks like it will be a blast once you get it done! Good luck!

[Brauhausbier]

Originally Posted by Blakebird

That looks like a good bike to start off with, it's seen a few muddy days but appears to be in pretty good shape.
I kept my white tank looking good with a Scotchbrite pad and a spritz of WD40

"only 35 outside" ? That would be a heat wave here the last couple weeks.



He raises a good question. Did you ride the bike much before tearing into it? If so, was there an issue with throttle response or something? Most people don't like the Keihin's "sticky slide" feeling off idle - you'll probably have people lining up to take that Mikuni off your hands

I've been reading plenty of material about the Mikuni Flat Slide on adv and TT which is saying that the Mikuni FS is no good and difficult to tune. I've only taken one ride at night on this XR before getting it home and torn down. I have no frame of reference really after this one ride here in the city. It ran ok, but could be much better.

I'm planning to hang on to the Mikuni for now and I'll get the OE Keihin cleaned up too. It will be easy enough to swap carbs in on this XR and compare the two when it's time.

Nice to have a thumper again and love how easy it is to get to everything. I've only been wrenching on my KTM950 the past couple of years which is very tedious at best.

[Brauhausbier]

Originally Posted by switch

Cheer mate. One question for ya: what's with the Mikuni carb? You're saying you're replacing it? Why? AFAIK it was supposed to be an upgrade to the stock one.

If you plan on improving in addition to restoring, you might want to check on GSMark's Oil Cooler thread. He's making XR 600/XL650/NX650 oil cooler kits! From what I've seen the stuff is as good as any OEM or aftermaket part, if not better.

Thanks Switch! For now I'm going to hang onto the Mikuni and see how that will pan out after I get the motor rebuilt. Thanks for the info on GSMark's oil cooler. I've been reading quite a bit about about oil starvation in the XR600 head and that mod sounds like the way to go!

[lionsroaar]

Originally Posted by Brauhausbier

I've been reading plenty of material about the Mikuni Flat Slide on adv and TT which is saying that the Mikuni FS is no good and difficult to tune. I've only taken one ride at night on this XR before getting it home and torn down. I have no frame of reference really after this one ride here in the city. It ran ok, but could be much better.

I'm planning to hang on to the Mikuni for now and I'll get the OE Keihin cleaned up too. It will be easy enough to swap carbs in on this XR and compare the two when it's time.

Nice to have a thumper again and love how easy it is to get to everything. I've only been wrenching on my KTM950 the past couple of years which is very tedious at best.

Good luck with the Mikuni. I picked up the same kit from XR's only and was never able to get it to run right. It was definitely smoother just off idle (no sticking) but the Keihin ran better just about everywhere else. I've seen a slide mod thread/post somewhere about modifying the bottom of the Keihin slide to eliminate the sticking...Could be worth a shot.

[Brauhausbier]

Originally Posted by lionsroaar

Good luck with the Mikuni. I picked up the same kit from XR's only and was never able to get it to run right. It was definitely smoother just off idle (no sticking) but the Keihin ran better just about everywhere else. I've seen a slide mod thread/post somewhere about modifying the bottom of the Keihin slide to eliminate the sticking...Could be worth a shot.

Thanks LR! I'm more interested in getting into the motor and getting the frame painted in the next few weeks. I'll have plenty of time to see which carb (Mikuni FS or OE Keihin) will run best when the time comes. I'll look for that OE Keihin mod. I have not heard about that one. Thx Cheers!

[Luke]

There are two kinds of Mikuni TM carburetors. One type meant for two strokes, and another kind meant for four strokes. You've got a two-stroke one. It looks like different companies sell both for the XR600. Maybe that's the reason people have so much trouble tuning them. For the XR400, every company I've seen sells the four stroke version and people all love it (unless they care about fuel economy )



Oh, and you might look into getting the frame powdercoated instead of painted. OregonCoast jsut got his SL frame and some other parts powdercoated by someone in Tillamook and they look fantastic.

[Brauhausbier]

Originally Posted by Luke

There are two kinds of Mikuni TM carburetors. One type meant for two strokes, and another kind meant for four strokes. You've got a two-stroke one. It looks like different companies sell both for the XR600. Maybe that's the reason people have so much trouble tuning them. For the XR400, every company I've seen sells the four stroke version and people all love it (unless they care about fuel economy )



Oh, and you might look into getting the frame powdercoated instead of painted. OregonCoast jsut got his SL frame and some other parts powdercoated by someone in Tillamook and they look fantastic.

Thanks Luke Really think that my Mikuni is the one for 2-strokes? There are some XR's Only parts on this bike, and I was thinking this was the Mikuni FlatSlider carb kit they sell (with the custom linkage for the carb). May have to see if I can find a serial number on that carb tonight. Wierd stuff.

Thanks for the tip on Powder Coating! I'll give OC a buzz and see what's up. I was thinking it would just be too expensive to powder coat and opt for the rattle can.

I'm taking my suspension into Vancover tonight and dropping that off at Promotion Suspensions. MTBDemon reccomended these guys.
http://www.promotionsuspension.com/

[Luke]

Originally Posted by Brauhausbier

Thanks Luke Really think that my Mikuni is the one for 2-strokes? There are some XR's Only parts on this bike, and I was thinking this was the Mikuni FlatSlider carb kit they sell (with the custom linkage for the carb). May have to see if I can find a serial number on that carb tonight. Wierd stuff.

Yeah, XR's Only sells the 2-stroke version. The noticeable difference is that the 2T version has a single throttle cable that pulls directly on the slide like you have, and the 4T version has two cables that turn a pully/linkage thing that moves the slide. And, the 2T version costs a lot less.

There must be some sort of internal differences because they use very different sizes of jets, but I don't know what they are.

[Rhino-1]

Originally Posted by Luke

Yeah, XR's Only sells the 2-stroke version. The noticeable difference is that the 2T version has a single throttle cable that pulls directly on the slide like you have, and the 4T version has two cables that turn a pully/linkage thing that moves the slide. And, the 2T version costs a lot less.

There must be some sort of internal differences because they use very different sizes of jets, but I don't know what they are.

X2. That's a 2-stroke TM for sure (I run 2 TM34's that are identical to that on my Banshee, and a TM just like that was OEM on Suzook Quadzilla 2-stroke 500cc quads). I'd sell it and buy a 4-stroke TM or an FCR.