What Have I Done?

[Rman of 237]

Originally Posted by BexarWolf

Yeah, after spending a couple hours with Rman yesterday, I'd never question his abilities. I'm only questioning MY abilities to be able to tune it to where it needs to be. I've never owned a dirt bike, much less a carb'ed dirt bike so finding the sweet spot is a bit of a challenge. I'm just tickled that I've got it running without choke right now. And it's cranking on the first or second kick which thrills me.

Next will be finding a way to tone down the volume on it. I know it's a dirt bike and all but I'm doing some research on the WB e-series muffler to see if adding or reducing discs will help. I think there are 10 discs in it right now and from what I've found so far......more discs = more noise. But reducing discs = reduction in flow so that'll affect the carb tuning.

I was hoping to have it up and running by next weekend to take it out to Bastrop for a shake-down run but I think I'll still be tweaking the adjustments by next weekend. Working nights (and a second part-time job) sucks the life out of me so I end up with very little time to play with it. But when I do get it running the way it should be...............

OK, good, now get it hot and ride it around the neighborhood (obviously avoiding your cop neighbor friend), with the choke in the off position adjust the pilot screw to give you the highest RPM at idle, then back off the idle screw as needed. Put some time on it then pull the plug and show us what it looks like. Black is rich, white is lean. We'll mess with the jetting from there.

[BexarWolf]

Looks like my XR is going on the back burner this weekend.

My F650gs is having starting issues (love the first month of the first year they went to FI ) so I'm swapping the injector this weekend to see if that helps. Then it'll be off to LSBMW to get the software flashed.

What is it with me and fuel delivery systems?

[BexarWolf]

A month later and I FINALLY get to toy with the XR4. It took a little coaxing after sitting so long but she finally fired off.

idle.AVI - YouTube

idle.AVI - YouTube

Don't panic over the screwdriver under the tank. I was trying to adjust the idle without branding my hand. I still need to address the issue of it bogging down under quick acceleration. I know a pumper carb will cure that but I don't want to invest in a carb that cost almost half what the entire bike cost.

So far what I've done is remove the ear-splitting White Bros muffler and install an OEM one off Ebay. It has the removable end piece so I can open it up a little bit if I don't want to be USFS compliant (which I do).

I've ordered a decompression cable off Ebay and just received a combo decomp lever/clutch lever for an XR650. It looks like it'll be a nice, clean install. I don't need the decomp lever but it'll facilitate restarts when I flood it or dump it.

I'm still tweaking the air screw a little at a time but It's obviously running rich. Rich enough to make your eyes burn. So I removed the 162 main jet and put in a 158 main. It still reeks of unburned fuel but not as bad. The plug was black as coal so I'll be heading down to the parts store to install a new one and see how it's burning.

Slowly but surely I'm getting it dialed in. I'll probably beg Rman to let me bring out to his house one Saturday morning (along with a few gallons of his liquid of choice) to see if he wants to toy with it and teach me a few more lessons.

[Rman of 237]

Originally Posted by BexarWolf

Slowly but surely I'm getting it dialed in. I'll probably beg Rman to let me bring out to his house one Saturday morning (along with a few gallons of his liquid of choice) to see if he wants to toy with it and teach me a few more lessons.

Yeah, anytime. That black smoke in the vid ain't good. And keep in mind, putting the OEM back on made it all the more richer as well. You'll definitely need a smaller main.

[Rman of 237]

So...?? What's the word BexarWolf, how's the XR4 coming along? Have you leaned out the main? Plated it? Bring it out here and we'll .

[WoodButcher]

Funny that you bring it up. We were trading PM's in the we hours of the morning today. He indeed has done something, but I'll leave it to Tad to tell you about it.

[Rman of 237]

Originally Posted by WoodButcher

Funny that you bring it up. We were trading PM's in the we hours of the morning today. He indeed has done something, but I'll leave it to Tad to tell you about it.

Do tell.

[BexarWolf]

I haven't had a lot of time to mess with it lately. Family obligations, working overtime, etc. I have a couple of jets coming in the mail to try and lean it out and such as well as some misc parts and pieces.

However.....

I gathered up a little change and should have a Mikuni pumper on hand by the weekend.

[Rman of 237]

Originally Posted by BexarWolf

However.....

I gathered up a little change and should have a Mikuni pumper on hand by the weekend.

BWAHAHAHA!!!!! Now you're cookin' with propane! Seriously dude, that Mikuni will make it a completely different machine! Do you know how the carb is jetted? Call those guys at 'XR's Only' and they'll help you out.

[BexarWolf]

Originally Posted by Rman of 237

BWAHAHAHA!!!!! Now you're cookin' with propane! Seriously dude, that Mikuni will make it a completely different machine! Do you know how the carb is jetted? Call those guys at 'XR's Only' and they'll help you out.

Called them to order it and told 'em it was basically stock. The only "upgrade" so far is the Uni filter and the snorkel has been removed under the seat. He said they'll include a couple of extra jets so I can tweak it as necessary.

I'm stoked but it'll be a couple of weekends before I can get it installed and the bike on some trails. Next weekend is wiped out so maybe the weekend of 14th I might be able to get out to Bastrop and see what I've gotten myself into.

[owtcast]

I'm probably going to pull the trigger on one too. With the stock carb.... you can just tell it needs more.

[BexarWolf]

The transplant is almost complete

I have to run by CT PowerSports tomorrow to see if they have the rubber gasket that goes between the engine-side air boot and the carb and I need to get one of the bolts that holds that air boot. The one on the bottom was pretty well butchered last time I was in there and I should have replaced it then. I had to use vice grips to get it out and the head is toast.

Hopefully, tomorrow I'll be posting a video of it running.

[Rman of 237]

Originally Posted by BexarWolf

The transplant is almost complete

I have to run by CT PowerSports tomorrow to see if they have the rubber gasket that goes between the engine-side air boot and the carb and I need to get one of the bolts that holds that air boot. The one on the bottom was pretty well butchered last time I was in there and I should have replaced it then. I had to use vice grips to get it out and the head is toast.

Hopefully, tomorrow I'll be posting a video of it running.

OK good, now remember the 'pump' (accelerator pump) can be set to engage at almost any throttle position. I have mine set to engage at about 1/4 throttle. The pump linkage itself is kinda hard to explain so play around with it and it's pretty self explanatory. Also I may remind you, if you happen to pull the carb back off for whatever reason, pay attention to where the intake side of the carb is pointed when you twist the linkage or you might wind up with a facefull of gas. Don't ask! Better yet, just for fun, before you even install it, fill the bowl and exercise the cable linkage a few times to prime the pump and see for yourself. It'll shoot a stream of gas clear across the room!
Good luck and keep us posted.

[BexarWolf]

Originally Posted by Rman of 237

OK good, now remember the 'pump' (accelerator pump) can be set to engage at almost any throttle position. I have mine set to engage at about 1/4 throttle. The pump linkage itself is kinda hard to explain so play around with it and it's pretty self explanatory. Also I may remind you, if you happen to pull the carb back off for whatever reason, pay attention to where the intake side of the carb is pointed when you twist the linkage or you might wind up with a facefull of gas. Don't ask! Better yet, just for fun, before you even install it, fill the bowl and exercise the cable linkage a few times to prime the pump and see for yourself. It'll shoot a stream of gas clear across the room!
Good luck and keep us posted.

Thanks for that info. Although the carb and such is great, the instructions from XRs Only are a little on the minimalist side. Figuring out the cables as fun but not too involved. I'll have to figure out where the adjustment is for the pump so I can adjust that. I was a little concerned at first because I couldn't get the carb in square to where it would fit into the airbox side. Eventually I learned I could twist the carb to get it in straight.

I haven't tightened everything up yet. MAN I wanted to just put the 3rd bolt in as tight as I could and crank it up but I want to do it right. The rubber gasket looked like it stretched out a little and didn't fit into the groove of airbox. Then when I tried to jam it in and tighten it up, it cut the gasket.

More to come soon I hope (as long as CT PowerSports has a well-stocked parts dept).

[Rman of 237]

Sorry but I'm confused, what gasket are you talking about?

http://www.bikebandit.com/houseofmot...m3082#sch95982

If you can get the airbox manifold boot on the carb tight with the hose clamp then forget about any airbox gaskets, crank 'er up!

[AustinJake]

Originally Posted by Rman of 237

Sorry but I'm confused, what gasket are you talking about?

http://www.bikebandit.com/houseofmot...m3082#sch95982

If you can get the airbox manifold boot on the carb tight with the hose clamp then forget about any airbox gaskets, crank 'er up!

That's the truth, you don't want any material tearing off and flying thru the carb into the combustion chamber!

[Rman of 237]

Originally Posted by AustinJake

That's the truth, you don't want any material tearing off and flying thru the carb into the combustion chamber!

Are you being sarcastic? WHAT GASKET???? OK, I'm lost.

[owtcast]

Did you have that much trouble getting it in there after pulling the rear subframe? Or did you actually get it in there without pulling the rear off?

[BexarWolf]

Originally Posted by owtcast

Did you have that much trouble getting it in there after pulling the rear subframe? Or did you actually get it in there without pulling the rear off?

Naw, didn't pull the subframe. Just the seat and tank to get access then yanked out the old, plugged in the new. The only trouble was getting the carb twisted so that it didn't hit against the frame on the back side while trying to get it into the airbox fitting.

The gasket I'm referring to is a rubber o-ring that goes between the cylinder head and the rubber boot that attaches to the carb. It's #14 in this schematic.

http://www.bikebandit.com/houseofmot...m3082#sch91853

[Rman of 237]

Originally Posted by BexarWolf

It's #14 in this schematic.

Aha!! OK, that makes sense. Next time all you need to do is angle it in while squeezing the airbox boot aft with your fingers. It takes some practice but it will come out and go in without messing around with the intake manifold. Sometimes I use what I call my "dentist tools" which are nothing more than little hooks and straight or slightly curved awls to work the airbox boot over the lip of the carb when needed. Trust me, the XR4 is an easy carb install, try a DR200 with that little spring-ring(?) clamp thing sometime!