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DR650 simple carb mods / jetting - how to procedure with photos here!

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I found myself wanting to mess with my carb and started searching. And boy did I find more than I wanted to read :busted:

After reading most of the threads, I have found that I thought I understood what I needed to do but I found the lack of clear photos / instructions a bit disturbing. Manuals I have, threads, DJ kit instructions etc - all did not help too much as it was not very clear to me. Now that I did it all, yeah it makes sense... but why not create some clear photos so a newb like myself could do it?

So here it goes. I have created a how to procedure. It covers most of the stuff needed in most cases. I am not recommending any settings, there are much more qualified people to do this on this forum :busted: but those instructions should help you take the carb apart with enough confidence to actually get to the point where you put your new needle, new main jet or that extended fuel screw in.

The link to the ZIP file is here.

The direct link to a PDF with instructions and photos is here.

Have fun! And yeah - I put it together and it runs so I must have done something right. :thumbsup: Yup, this was the first time ever I took a carb apart.

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So, let's say I just want a bit more "oomph" in the low end, but would like to retain as much gas mileage as possible. Could I shim the stock needle, drill the slider and drill the stock airbox without running into any other issues?

I'm a newbie too, just got my bike a couple of weeks ago. I use it to commute to and from work, but as I said above, I would like just a bit more grunt at take off.

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So, let's say I just want a bit more "oomph" in the low end, but would like to retain as much gas mileage as possible. Could I shim the stock needle, drill the slider and drill the stock airbox without running into any other issues?

I'm a newbie too, just got my bike a couple of weeks ago. I use it to commute to and from work, but as I said above, I would like just a bit more grunt at take off.

That is pretty much my approach for now too. I think you'll need to also adjust the fuel screw a bit if you open up the airbox (you could just de-snorkel it as the first step). I bought a DJ kit but for now did not install any of it.

If you commute HWY a lot, you might want to consider 16T front sprocket too. I installed that this past weekend too. Kind of a pain in the butt to install through as I had to take off the back wheel to get enough chain slack to be able to put the chain on the new sprocket...

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awesom thread, how much difference did this make or if u know how much difference does drilling airbox make? looking for a little more bottem end

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Cool, I just got done adding a .035" shim, drilling the slide and removing the snorkel. I was waiting for my wife to come out and give me a hard time about working on the bike at midnight on a work night :thumbsup: (between the bike, the Jeep and whatever welding project I've got going on, it seems I'm always in the garage after bedtime).

My only question, how the heck do you turn the pilot screw with the bike running? I drilled out the brass plug and turned the screw 2.5 turns out, but it sure does smell rich (but it does idle better). I'd like to adjust it while running to dial it in just right, but I don't have a screwdriver that'll fit between the carb and starter. Any tips here?

I did take the bike out after I got done to make sure it was running ok. This was the first time I was able to get the wheel up without having to bounce the bike first or slipping the clutch. I put `er in first gear, got rolling a bit, leaned back and rolled on the throttle and the wheel came up enough to surprise me.

It does seem to have more power through the gears on the short run down the highway I took. So far, I'm happy, just wondering about the richness at idle.

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My only question, how the heck do you turn the pilot screw with the bike running? I drilled out the brass plug and turned the screw 2.5 turns out, but it sure does smell rich (but it does idle better). I'd like to adjust it while running to dial it in just right, but I don't have a screwdriver that'll fit between the carb and starter. Any tips here?

That's where Jesse's extended screw comes in... :thumbsup: I guess you'll need a small screwdriver with stock screw, not sure of any other ways...

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I used a short screwdriver drill motor bit in a 1/4" socket (Tape it in place or you WILL be fishing it out from the bottom of the motor at least once:)). This was a 1/4" drive socket and it helped to put a 3/8" adapter on it to get a bit more diameter & length to manipulate it. Worked best for me to twist with my right fingers while holding vertical pressure with my left forefinger. Use a rag to keep from burning your hands.

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I used a short screwdriver drill motor bit in a 1/4" socket (Tape it in place or you WILL be fishing it out from the bottom of the motor at least once:)). This was a 1/4" drive socket and it helped to put a 3/8" adapter on it to get a bit more diameter & length to manipulate it. Worked best for me to twist with my right fingers while holding vertical pressure with my left forefinger. Use a rag to keep from burning your hands.

I tired that, I don't have a bit small enough in diameter to go into the whole that the pilot screw is recessed into.

I guess I need to go get a smaller bit.

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No offense Cipher, since I know by experience it's easy to get disoriented working on the carb upside down with limited visibility, but make sure you're working on the right opening. The diameter shouldn't matter because the depth of the screw is only about 1/4", so as long as the bit has a narrow blade you should be OK.

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No offense Cipher, since I know by experience it's easy to get disoriented working on the carb upside down with limited visibility, but make sure you're working on the right opening. The diameter shouldn't matter because the depth of the screw is only about 1/4", so as long as the bit has a narrow blade you should be OK.

It's the right hole, but all of my drill type flat head bits are too big for the hole (lots of joke there). The depth isn't the issue, my bits are too wide.

Jeez, guys. Just spend the $15 and get the extended fuel screw from Jesse.

Tell you what, you buy me one, it's only $15...

I have a whole slew of other "hobbies", the bike is my commuter.

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My wife has got a whole slew of "better" things for ME to spend My money on than a $15 screw (as she calls it)!!!!

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Huge thumbs up to you Bigboy for this write up. :ride:

I would never have tried this project without a how-to like yours. I know I've read it a million times, but the difference this project makes to how the bike runs is unreal!

Thought I'd share a couple of my observations for anybody else that wants to undertake this project.

1. I was unable to remove the throttle cable bracket, the screws were just too darn tight. I ended up loosening the nuts that hold the cables on and took them off. To make sure I got them back on right, I just counted the # of threads showing at the top.

2. The other sticky spot was removing the throttle cable. It was at such a funky angle, I just couldn't get my wrench around it....No problem though, I just left it attached and did the whole job without removing the carb from the bike. With two people doing it, it's not too bad at all.

3. When it was time to cut open the airbox, my buddy suggested we try cutting it without pulling it out. So we ended up taking the blade off of my hacksaw and starting from the snorkel hole, just cut out different pieces until most of the top was off. We didn't get quite as much off as if we had removed it and followed Jessie's instructions, but we got at most of it. Pretty easy. Then we cleaned up the rough edges with razor blade. Simple as that.

Now my DR really thumps. Thanks again!;)

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My wife has got a whole slew of "better" things for ME to spend My money on than a $15 screw (as she calls it)!!!!

that sucks for you whipped boy.

i'm married but spend my $ as i please.

the carb screw is a great addition to fine tune things under different ridding conditions. it's worth $15 for ease of use.

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http://www.sears.com/shc/s/p_10153_12605_00947641000P?BV_SessionID=@@@@0891862211.1114748786@@@@&BV_EngineID=ccfhaddehjiflddcegecegjdghldfoo.0&vertical=SEARS&sid=I0093600100004900085&pid=00947641000

Huge thumbs up to you Bigboy for this write up. :ride:

I would never have tried this project without a how-to like yours. I know I've read it a million times, but the difference this project makes to how the bike runs is unreal!

Thought I'd share a couple of my observations for anybody else that wants to undertake this project.

1. I was unable to remove the throttle cable bracket, the screws were just too darn tight. I ended up loosening the nuts that hold the cables on and took them off. To make sure I got them back on right, I just counted the # of threads showing at the top.

2. The other sticky spot was removing the throttle cable. It was at such a funky angle, I just couldn't get my wrench around it....No problem though, I just left it attached and did the whole job without removing the carb from the bike. With two people doing it, it's not too bad at all.

3. When it was time to cut open the airbox, my buddy suggested we try cutting it without pulling it out. So we ended up taking the blade off of my hacksaw and starting from the snorkel hole, just cut out different pieces until most of the top was off. We didn't get quite as much off as if we had removed it and followed Jessie's instructions, but we got at most of it. Pretty easy. Then we cleaned up the rough edges with razor blade. Simple as that.

Now my DR really thumps. Thanks again!;)

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It's the right hole, but all of my drill type flat head bits are too big for the hole (lots of joke there). The depth isn't the issue, my bits are too wide.

Tell you what, you buy me one, it's only $15...

I have a whole slew of other "hobbies", the bike is my commuter.

if you can't afford $15 to help out with your bike then you're over extended on buying stuff for your "hobbies"

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