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Discussion Starter #1 (Edited)
At sea level, my 132.5/.060"/2.5turns setup was already a little on the rich side, though it was fantastic during the colder, winter months. Fred's stomping grounds, however, not so good. Fred HQ, at 5100', was just ok, but at the 6k and 7k marks, I was basically just wrestling a polished turd. I was so frustrated with the bike's performance that weekend, I decided that +-$100 was worth experimenting with the Dial-A-Jet.

This past weekend, I finally got off my arse and put the stock 126 in, removed the 2 excessive shims, and put the DAJ on. Aside from trying to round out the carb's two top cover screws and having issues trying to get the carb back into its boots, all was fairly easy and issue-free. So the setup is now: 126/.040"/2.5, notch 4 of 5 on the DAJ, where richest setting is 1, leanest is 5. The bike hasn't run this well since swapping out my pipe. Heck, since I got it over a year ago. Everything, to me, feels dead on - initial throttle, mid, and WOT. Starts easy (I think I've only ever used my choke once or twice, ever), no hesitation, no surging, and no decel pops. Even if it never sees altitude again, I'll consider the $100 to be a win. Looking forward to seeing what happens, if anything, to gas mileage. In theory, since it's running leaner but taking more as it needs it via vacuum, I should hopefully see a little bit of a difference.

Since the DAJ is currently running on the second to last leanest setting, I've ordered a 122 main jet. My hope is that it will allow me to run with the DAJ at the second to last richest setting at home, allowing for a click richer in colder weather, and 3 clicks leaner for altitude (each click, from what I've read online, should be good for about 2000ft or so).

Also, for poo and giggles (mostly giggles), I've ordered DAJ's TPI Valve, which basically gives the air-box a convertible effect - a small hole in the air-box cover that can be opened up or closed. This is rumored to be able to lean out the bike by one or two jet sizes, when/if needed. We shall see.

I'll report back as I: put the 122 on, put the TPI on, actually test at altitude (Fred!), or learn more about things as they happen in relation to the above.

Random notes:
1) Placement. They recommend between 10 o'clock and 2 o'clock position on the carb/intake. Mine is more at 9:10 for easy access. I'm sure it's a gravity assist thing, and I'd imagine anything outside of 3pm to 9pm should be more than fine. Seems ok where mine is at.
2) Placement part 2. Boot vs carb.
Available space on boot; not really any space on carb.
Tools for boot (included in kit); no tools to drill out carb
Fixing any screwups. Duct tape, or worst case, new boot, should be easier/cheaper than new carb.
3) DAJ fuel tube acts as float level indicator.
4) (Pictured) Currently running without its (separately purchased) snorkel. Pain free testing and street riding. The snorkel will go on before the bike sees dirt.
5) As per Thunder Products' site, "NOT legal for sale in California on pollution controlled motor vehicles except on vehicles used for closed course racing only or in other states where similar laws apply. For off-road racing use only". I had to fill out a CARB (California Air Resource Board) waiver, promising that "the products I am purchasing ... will be used only in closed course competition such as motocross or drag racing or closed course events in accordance to CARB policies" twice; once for the DAJ, and once for the TPI.

DAJ1.jpg

DAJ2.jpg

DAJ.installed.jpg

carbDAJ.png
 

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You sure have my attention!

I checked out the website and what I gather you set your carb up to run lean and then use DAJ to richen it up a little bit at a time until it runs well. Check your spark plug and see how it looks. Easiest way to tell how if it is running to rich or lean.
 

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Nice write up George, now you are ready for a little "closed course competition" up here or on Josh's upcoming ride. I like the way tubing acts like a float bowl level indicator. What is especially appreciated is that you have demonstrated that the modification is both straightforward and results in immediate gratifying results without a lot of fine tuning. Many thanks even though you have now added one more thing to my wish list. And Just as I was thinking my bike will be the cat's meow once Brian's gift of kick starter gets installed....darn forrum and it's creative inventive members, always one more farkle to crave.
 

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Discussion Starter #6
I checked out the website and what I gather you set your carb up to run lean and then use DAJ to richen it up a little bit at a time until it runs well. Check your spark plug and see how it looks. Easiest way to tell how if it is running to rich or lean.
This is exactly how it works. Putting the stock 126 on leaned it up enough to use is around my stomping grounds, but not enough for its intended use: altitude. 122 is on its way, and I'll have no issue with ordering a 120 if the 122 doesn't put me at the second to last rich setting for home. I may eventually do a spark plug check, but between a year on this one already and the weekend in Fredtowne running really rich, I think this plug is outside of it's "tell me whatcha know" period.

Nice write up George, now you are ready for a little "closed course competition" up here or on Josh's upcoming ride. I like the way tubing acts like a float bowl level indicator. What is especially appreciated is that you have demonstrated that the modification is both straightforward and results in immediate gratifying results without a lot of fine tuning. Many thanks even though you have now added one more thing to my wish list. And Just as I was thinking my bike will be the cat's meow once Brian's gift of kick starter gets installed....darn forrum and it's creative inventive members, always one more farkle to crave.
Definitely eyeballing Josh's ride, or any other when I can start taking a Friday off, again. When it comes to mechanicals, if I can do it, pretty much anyone can do it! :) And yes, I took it around the block twice - once in center, once towards rich, and then for a trip across the City on once towards lean. Liked it too much where it was to properly rule out the full lean setting.

Totally envious of that kickstarter! And yes, we all know there are always farkles on the list!
 

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Looks like a nice addition to your TW! Josh, When is your upcoming ride? Have you set a date yet?
 

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Any more updates Andrew? Figure you probably haven't had it at altitude yet, but have you pulled the plug to check burn conditions?
Thanks Josh
 

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Discussion Starter #10
Have not checked on the plug. On leanest DAJ setting, and think it needs to go further. Have 122 and 120, but didn't make the time to put them on during the three days of festivities. I'll probably start with the 120.
 

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Discussion Starter #11
Quick update. I've been running under-inflated since the ride at Fred's. Just did my first measurable fill-up since the DAJ install. 57mpg. Previous setup with proper tire inflation I was getting 49/50mpg. :eek:ccasion14:
 

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Thanks for the Info I'll have to check it out.
The bike runs fine I haven't put the DG pipe on yet & I haven't taken it to high altitude yet ,
but some friends said I will have to jet it.
Thank you
Robert
 

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Temperature and elevation adjustment chart.

Jetting.jpg

For example:

At a temperature of 30 degrees C (86 degrees F) and an elevation of 3,000 meters (9840 feet) the main jet would be corrected as follows:

125 x 0.92 = 115

This is only a starting point! When in doubt go one size larger. Always take plug color readings when re-jetting!

And please remember that altitude and elevation are two different things. Altitude is typically only used to describe the height of an aircraft in flight. Elevation is usually used to describe the height of the ground or a feature fixed to the ground.

Please be careful when changing jetting and on many rides it is not all that necessary because you will probably be returning to a lower elevation on your way home. And going back to a lower elevation with a smaller main jet will probably result in engine damage.

This chart does not take into account any engine, ignition, exhaust or airbox modifications you might have made.
 

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Discussion Starter #14
Sunday I put on the 120, backed off the mixture to 1.75 turns, and shims down to 2 (.020"). Richest DAJ setting was way too lean.

Last night, put the 122 on, 2 turns. Things are running great right now, possibly still a teeny bit lean low/mid-throttle (mixture? 3rd shim?) - most likely will not do anything more with it before this weekend's ride. Still trying to talk myself into installing the TPI before the trip - it's only existence, for me, is for when elevation exceeds max lean of the DAJ.
 

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Just a quick little tip for float bowl screws: Use a small flat screwdriver (not Phillips) and you won't round them out :)
 
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Discussion Starter #16
And when you remove them with the flat screwdriver, immediately replace them with metric allen heads ;)
 
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George, I look forward to riding with you and the gang this weekend at elevations from maybe as low as 5500 ft along Carson River to 8700 ft elevations on passes, ridges, and Highland Lakes. Proposed tour shall have us going up and down quite a bit. (Our altitude should not exceed a couple of inches and submerged depths should not exceed axle deep.Haha) Be nice to see effect of Dial-a-Jet over varying elevations as you leave rest of us blubbering and sputtering in your wake.
The TPI claims to lean out air/fuel mixture by opening up air filter housing to facilitate more air through carburator have me skeptical. Problem at elevation is decrease in partial pressure of oxygen, not volume of air. I was taught that fluid dynamics theory states via Bernoulli equation that greater air flow rate through carburator = greater air speed = lower pressure = greater suction at jet orifices = increased fuel delivery to match increased air flow rate = maintainance of same air/fuel ratio established by jets. This is why fuel injection systems have mass air and/or o2 sensors to measure data so engine management systems can alter air fuel mix thus automatically accomplishing what Bananachunks is doing manually with Dial-a-Jet. So this is another case where the proof will be in the pudding, whether practical knowledge and experience triumphs over theory. Maybe TPI benefit is like other elevation independent engine hot rodding, try to make more power my processing more air/fuel mix through engine, even if it is a sub-optimal air/fuel mix. After all our internal combustion engines are essentially air pumps.
 

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Discussion Starter #18
I still need to get/make a fuel mixture screw - half my problem last time was it was just running like poo in general. The other half was not being able to let off the gas without stalling. The other half was me. :D
 

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George, Perhaps the other half of your problem was you had 3 halves going at once, one half too many. I have herd of going off half-cocked, but three halves is a new one.:p
I too would like a readily adjustable by hand mixture screw. Maybe drill hole in needle screw's base to silver solder an allen wrench to create a handle and then try to adjust it without getting burned. Isn't it getting crowded at your carb with Dial-a-Jet installed plumbing? Might make accessing mixture screw a greater challenge than it currently is on oem bikes.
 

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Discussion Starter #20
Three halves make a whole! Because science! That's my story...

Not too badly crowded down there (though I'm still getting used to how much less room there is with the Clarke tank vs stock). Putting the DAJ air snorkel on may be an interesting task, but a mixture adjuster should be fine. I know there's someone on the forum that (used to) put together just what you described if you send them a pilot, I just never pulled the trigger on it.

I'm definitely looking forward to seeing how the DAJ does this weekend. I have high hopes, but low expectations.
 
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