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Dave's Mod and the Smog stuff

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Okay, I finally have all the jets to do the Dave's Mod to the carb. While I'm at it I also plan to remove the smog stuff. I am pretty good with bikes and have had many a carb a part. Plus I do a really good job of mapping out hose connections before I start removing things.

So here's my question, what kind of performance will I get?

I will probably do the exhaust grinding, too, if someone will give me a better pic of exactly where in the exhaust system I am grinding? Is it where the exhaust comes out of the head, where it connects to the muffler? Where?

All this is plannned for Saturday morning.

BTW - anyone have the diameters for the washer for the needle (ID and OD)?

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As far as the grinding goes, when you take the header off, you will see the weld where the header bolts to the head. Be careful and don't grind too much, you don't want to weaken the weld. I have done the grinding on the smaller bikes but not the 650 but it should all be basically the same routine.

You just want to remove the excess weld and smooth it out.

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Looks to me like no one really does the Dave mod. 49 looks and no response? Come on.

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EZ there CRF dude. Many here have done daves mod we just forget the Id and Od of the washer. Most use a #4 washer. I did a thread search before I picked up my washer at the local hardware store. You gain a little umph and a whole lot of throttle response. The bike just seems more rideable after the mod. The most popular spot to pick up a washer was a hobby shop. I think Dubro or something like that is a brand of # 4 washer that works well.

Search the threads--do the mods--be happy:thumbsup:

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Thanks BRP Chaos. I appreciate you taking the time to answer. I did a search before I posted but just wanted a bit more input before I tear into the beast. So, again, thanks for taking the time to answer.

BTW - I have the same year, make, model bike as you. Just got it used with 660 mile on it. Yeah, I'm smilin'!

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The size id and od of the washer would be good to know.

I am interested in the differance as well as how many people leave the smog stuff on???

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I would dare say hundreds have done the mod but i'd probably get slapped. Most likely thousands. If i have the need to take my carb apart again i will surely mic the ID,OD and post it. Seems to be the most asked question pertaining to that mod.

Looks to me like no one really does the Dave mod. 49 looks and no response? Come on.

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One little bit of advice for an uncertain future.

California is trying hard to start some kind of motorcycle smog program. Whatever you take off, put it in a box, label it, and put it on a shelf in the garage. Don't just toss it. While it would suck to have to reinstall it for a smog test, it would suck a lot more to have to buy it all again so you can put it back on.

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Just did the Dave Mod, Uni Filter, smog removal. Yep. It is a whole new bike. Not as snappy as my CRF but so much better than stock. I wish I had better confidence in the turns. But that will come.

It's all boxed up and ready to be put back if.....

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Done allready CRF??? After I did mine I didn't realize one of the hoses was a vent line and went looking all over where to hook up the final hose. It really improves ridabilily doesn't it. Soooo where did you find the washer?

The bike will never be a CRF but it is major fun on fire roads, twisty canyon roads and yes I even muscle it around on single track trails from time to time. I saved the old smog stuff but hopefully won't have to put it back on.

We don't even smog check cars where I live... yet!

Anyway I'm sure you will like the improvement in performance/ridability. Enjoy your pig.

CC

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For those of you Jonesing for exact measurements of a quality Daves mod washer... here you go. http://www.4strokes.com/forums/topic.asp?TOPIC_ID=27354&SearchTerms=dubro

From that attachment:

Other folks have had luck with Du-Bro #4 flat washer cat.no.323 available at hobby shops or online e-tailers.

#4 Specs = .13 x. 278 x .029 (ID x OD x Thickness)

Here's the forum link:

4Strokes.com Dubro Washer Info

Same hobby supply sources may have the nominal thicknesses you quest.

~Ecks

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From that attachment:

Other folks have had luck with Du-Bro #4 flat washer cat.no.323 available at hobby shops or online e-tailers.

#4 Specs = .13 x. 278 x .029 (ID x OD x Thickness)

Here's the forum link:

4Strokes.com Dubro Washer Info

Same hobby supply sources may have the nominal thicknesses you quest.

~Ecks

Thanks for the info.

I found that those washers can actually vary up to .005" in the same box sometimes.

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