How Big and Light can you make a DR350?

Discussion in 'Thumpers' started by gmansyz, Jul 7, 2013.

  1. gmansyz

    gmansyz Adventurer

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    Okay, how large a displacement can you make a DR350SE? With a custom piston and sleeve, will it go to 93mm or 95mm?
    And, with newer RM250 inverted forks and a different swingarm, will it be able to get it down to 250 pounds?
    Tnx
    Greg
    #1
  2. dankatz

    dankatz Been here awhile

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    Can't comment on engine size, but weight...not sure that much weight can be lost. You can change the battery (assuming SE) and exhaust to lighter ones and would probably save about 20lbs, but everything else....ounces here and there
    #2
  3. oldenuf

    oldenuf Been here awhile

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    You are leaving this rather open. Are you planning on adding a rack, skid plate, and other "farkles"?

    Then the DR350 may end up a few pounds more than when you started.

    Art
    #3
  4. itsatdm

    itsatdm Long timer

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  5. Kommando

    Kommando Long timer

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    The biggest I've seen is around 440cc. You can probably also boost power with a hi-compression piston, a custom camshaft, an uncorked airbox, a pumper carb, and by cleaning up the head.

    Shave weight with a lighter muffler, fueltank and cap, lighting, mirrors, bars, gauges, and battery. 20lb is usually do-able without getting crazy about cutting lightening holes in everything. You might be able to do 250lb dry, but curb weight is likely to be considerably more. Shave a little more by trimming off un-needed brackets, switches, mudflaps, and other parts. Do you ever use the passenger pegs? I do, on my 650, but most don't seem to. How about the flimsy helmet lock?
    #5
  6. gmansyz

    gmansyz Adventurer

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    Tnx for all the answers. And the link. Looks like I will buying a lot of goodies from ProCycle.
    Yes to a skid plate and lighter battery and the rest. I used to make pistons and will need to check how far the stock cylinder can go before having a real big pistons made. Only if I do, I don't know what I would do with the other three pistons? I wouldn't get to high with the compression. Maybe 9.5:1 so I can use regular gas and easy starting. Porting, big valves and definitely a camshaft. I like the pumper carb as well but would experiment with the 650's 40mm CV Mikuni first.
    And yes, I would cut/remove a lot the brackets and junk that is not needed. Helmet lock and pass pegs. Would be nice if the bike were lighter than my wifey and beside, I may need the passenger space for carrying extra stuff and gas. May keep the rear fender extender as if I ride in mud, it will be everywhere and the flat could reduce it a little.
    Headlight? How bad is the stocker? And the gauges? A tach is always nice but what could you replace the speedo with? I would try to keep the electronic stuff down to a minimum. Battery would be an easy weight reduction. But I would also ad the kick start option so I gain a little there.
    So, I will be looking for a project after I move at the end of the month and will keep yo'all posted.
    Tnx
    Greg
    #6