the DR650 thread

Discussion in 'Thumpers' started by sleepywombat, May 1, 2006.

  1. Tall Man

    Tall Man Priest, Temple of Syrinx

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    That was my first thought, but they meet the standard of "adjustable", with no "non-" attached.
    So it would seem that additional surgery is necessary if the self-adjusting function eventually fails, to the point that ticking is evident? Just want to learn here.


    There absolutely should be more emphasis on this avenue as a legitimate endeavor for high school students.
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  2. Schmokel

    Schmokel I got peed on today.

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    Yep. Trade school or Coast Guard. We'll be pushing those avenues for sure.
  3. Kommando

    Kommando Long timer

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    A few motos have non-adjusting valves. The bigger Honda Nighthawks are like this, and were also offered with shaft drive. They make for an extremely low maintenance moto.

    A lot of public schools can be pretty good too, but then you're typically paying quite a bit in property taxes to live in that school district.
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  4. Kommando

    Kommando Long timer

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    USAF tends to treat their troops decently too, but there are still civilian jobs out there that offer OJT as well as educational benefits. Coach the kid in getting things like a CDL, a GROL from the FCC, an EMT license, a 2nd-degree blackbelt or two, and maybe a welding cert. Some of these can be trained for before they're even out of HS, then the cert can be tested for at 18. Jobs that offer OJT and other educational benefits may almost find them. They may even be ready to start their own side business too.
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  5. procycle

    procycle Long timer

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    Yes, repair or replacement of parts if something goes wrong but there is nothing in there to adjust.
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  6. guavadude

    guavadude Dirt Nap Enthusiast

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    What size are the stock main and pilot jets in the BST40?

    I installed the JD Jet kit...red needle at 4th clip position, 145 main jet and the JD 42.5 pilot jet, uni air filter, and back to stock exhaust. I had to close the air box back up to the snorkel sized hole to eliminate the surging at low rpms. Bike seemed to be running well through the entire range but I did have to open up the fuel/air mixture a bit up from 1.5 turns. Hard to tell where it ended up since those extended screws don't have a marking. I just tweaked until it ran right. I'm waiting on the stock carb vent snorkel to arrive so that could make a difference in the settings and how open the air box ends up.

    It ran REALLY close to the DR I rode with the FCR carb. Not quite as instant on acceleration but plenty for me.

    Since I'm heading up to CO altitude next month I'm wondering if I should put the JD 140 jet in like they recommend or put the stock jet back in? What about the pilot jet, does it stay the same? I'll give them a call but figured someone has first hand experience. thx
  7. ER70S-2

    ER70S-2 Long timer

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    Stock main is 140, stock pilot is 42.5. The pilot is good almost everywhere and rarely needs to be changed.
  8. cyberdos

    cyberdos Easy Bonus Loop

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    What do you have in yours? Should I be re-jetting for, say, if I want to go to a place like, maybe, Ouray? :deal

    I wasn't going to mess with the carb but I have all this time to think about it so. :*sip*

    It would be easy enough for me to grab a few jets and bring them along.
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  9. guavadude

    guavadude Dirt Nap Enthusiast

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    Called and talked to JD. He said use their pilot jet, although it seems to be the same size, they provide one because they don't know how messed up the stock one is. For altitude he recommends putting the 140 main jet in, red needle on third clip and adjust mixture as necessary.
  10. thump!

    thump! Adventurer

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    Engines with hydraulic lifters do not require valve adjustment. Essentially all American made OHV engines had hydraulic lifters (not sure about the American OHC ones - never had one). My Honda Pacific Coast had overhead cams and hydraulic lifters - i.e. no valve adjustment needed.
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  11. Tall Man

    Tall Man Priest, Temple of Syrinx

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    [​IMG]

    I remember when I originally learned of the distinction between interference and non-interference engine designs. That is to say, will or won't the valves make contact with the pistons when the timing belt breaks. With that in mind, I do still wonder why interference designs continue to be used. I'm sure there's a valid reason or 3.
  12. Mongle

    Mongle Knuckle dragger

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    Correct. It has some type of hydraulic lifter in it. Which means 1 of two things: 1. The lifter is dying and can't keep up or 2. there is so much wear the lifter has ran out of travel. Either way you can't get the head off without taking the motor out. No simple job on that pig.
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  13. cyberdos

    cyberdos Easy Bonus Loop

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    Maybe my VFR has hydraulic lifters because I haven't checked the valves in 95k miles. :lol3
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  14. Mongle

    Mongle Knuckle dragger

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    I would say 95%...not all. Most performance stuff from the 60's was solid lift. And OHC engines have several different types of hydraulic adjuster. Some performance stuff like the WRX are still solid lift. Most of the marine 4 stroke outboards run solid lift as well.
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  15. NC Rick

    NC Rick Cogent Dynamics Inc

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    You know, funnily,I was thinking the same thing. I have an FCR and from past experience, I think BST or FCR equipped DR650s need some adjustment once altitudes much above 10k come into play. I think my DR made like 6 hp up at over 12k.
  16. Mongle

    Mongle Knuckle dragger

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    Mathmatically, a 34HP DR would have 22HP at 12K. When you don't have a lot to start with a 33% drop is a LOT! Doesn't help when you are huffing trying to make the bike do more. :lol3
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  17. ER70S-2

    ER70S-2 Long timer

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    If you get bored, a 135 MJ runs cleaner for those few times yer WFO, like every uphill. My snorkel is out and I have a 2nd snorkel sized hole in the top of the airbox. An extended idle mixture screw might help at the summits but I've never had to mess with mine. If your needle is shimmed, you could take the shim out. If yer runnin' a jet kit, I don't hava clue. :scratch IIRC you also have a HC piston and a cam, so my stock carb/engine recommendations could be useless for you. :scratch

    I'll gear down to a 14t / 42t cause @thump! has had good luck with it. 17t / 42 izn't gonna get it. :nono

    Stock DR up to 14k feet (paved). Note that the camera video is showing about 500 ft. lower than true altitude.
    [​IMG]
  18. Mongle

    Mongle Knuckle dragger

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    As for re jetting with altitude: less air is being drawn through the carb so less fuel is being pulled through the jet. Jetting does "help" but there is no curing HP loss at elevation without forced induction.
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  19. cyberdos

    cyberdos Easy Bonus Loop

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    All 4 loops I have in mind take us over 10k feet.

    I'm jetted for 1,500.
  20. thump!

    thump! Adventurer

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    My stock jetted BST40 ran clean all the way to 13+K feet. A friend's DRZ400 with a DJ kit for <1000 feet would not run up there. My DR350 with a flat side carb required re-jetting. I don't mean the DRZ and the DR350 ran poorly - they would not run enough to propel themselves.
    [​IMG] rejetting at Imogene Pass

    OTOH, the DR650 I rode in Ecuador ran fine at 14.5. Down on power yes but never missed a lick. CV carbs have some ability to compensate when running on the slide/needle but at the extremes (pilot circuit and main jet) don't will likely be too rich. This is one of the main reasons I run the BST. On several trips my bike has been ridden from just above sea level to almost 14K feet. Rejetting every 2 or 3 thousand sux.
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