DR350 Adventure Bike Build

Discussion in 'Some Assembly Required' started by hellotimmutton, Sep 9, 2019.

  1. hellotimmutton

    hellotimmutton Been here awhile

    Joined:
    Oct 24, 2016
    Oddometer:
    174
    One day whilst having a beer with a motorcyclist buddy, he told me I should watch "Long Way Round". After binge watching it one quiet weekend, followed not long after by long way down, I had decided I must also do some long distance adventure riding. I had the hardest time deciding what bike I wanted, until I discovered Mondo Enduro and fell in love with the DR350.

    After a while of searching (theyre rare in the south east corner of Aus) I found a 95 model that had seen a lot better days. The airbox was cut open, a crappy pipe that did bugger all was practically glued on and the battery was way under spec. I got the bike legal, then thumped around on it for a bit, getting in way over my head in the mountains. Had a shop swap on an eiger cylinder, weld the balancer pin and swap in the 5th & 6th gear from a '91 dr350s transmission I scored cheap, which took forever because I'd been given the wrong piston rings and had to wait for the right ones to ship from o/s, and then thumped around it some more.

    Now Im in the process of tearing down the bike. Ive decided to swap the full DR250s transmission as the gap between 4th and 5th is horrendous (dont know why I didnt just do that originally) and want to get the piston flattened to reduce the compression ratio down from 10.5:1 so I can take it places with crappier fuel. Also considering an early model clutch basket with a late model 1st gear to make it a true wide ratio. And a new exhaust, since the current one is trash.

    Once I'm done with the engine, the plan is to upgrade the suspension and give it a larger tank and luggage rack, as well as some other odds and ends.

    This is how it sits currently. Feeling a bit in over my head, hoping I dont royally screw it up

    [​IMG]

    [​IMG]
    #1
    mentolio, DRZ RIDER, Pezz_gs and 2 others like this.
  2. mADVta

    mADVta Adventurer

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    Dec 19, 2018
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    26
    Location:
    Wroclaw, PL
    Looks like mine DR just few months ago :) Though, I didn't do so many swaps and upgrades. Made just enough to bring her back to life and make her more suitable for long distance travels.

    Will be lurking around, looks like I can learn something new 8)
    #2
  3. AntónioPereira

    AntónioPereira Adventurer

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    Jul 9, 2017
    Oddometer:
    17
    Location:
    Leiria, Portugal
    I'm in for this one! ;)
    #3
  4. brownvv

    brownvv Been here awhile

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    colorado
    Seems like most people just instal the 5th and 6th from the 250. I did the whole 250 transmission and the spacing feels perfect. I even used a later model 350 first gear to widen the transmission a tad more
    #4
  5. hellotimmutton

    hellotimmutton Been here awhile

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    After reading a couple build threads and the main owners thread, I had a massive list of things that could be done, and then had to go through and ask myself what was practical and what would be overkill. I'm hoping I settled somewhere in the middle

    Good to hear someone else has done it with success, there was a part of me that was worried that taller 2nd - 4th would negatively affect off-road performance. I'm hoping that this will make highway riding more comfortable while retaining my ability to ride trails, at the expense of racing performance (not an issue for me)
    #5
  6. brownvv

    brownvv Been here awhile

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    1st and 2nd are not taller. 3rd-6th are.
    I have a 441 kit in mine. I do highway and trail without changing sprockets most days
    #6
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  7. NorthernTraveler

    NorthernTraveler Long time Adventurer

    Joined:
    Jan 1, 2009
    Oddometer:
    683
    Location:
    The Big Mitten
    Couple things for the suspension -

    Try to get a set of 1987 RM 125/250 forks. The are still 43mm, but are cartridge forks. The front axle is 17mm, you can swap the bearings in the stock DR front wheel but you'll have to make a new spacer. The stock brake caliper works. Get a set of Honda XR650L stock fork springs, they fit perfectly and are stiffer - .44kg, which is about right with a larger tank.

    For the rear end, get a dirt model shock. The dirt model is both compression and rebound adjustable. Add a Race tech gold valve if you like.

    I have a 450 cylinder kit and I don't use it. It pulled like a tractor on the bottom end but didn't want to rev out. The 380 or 400 is about right.
    I have 3 DR350s tight now - 2 1990's dirt models and a '96 SE. The '96 has the above suspension, Acerbis 4 gallon tank, and stock rear luggage rack.

    Have fun!
    #7
    hellotimmutton and DRZ RIDER like this.
  8. hellotimmutton

    hellotimmutton Been here awhile

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    Engine disassembly is going slow. Got the magneto off but need to get my hands on a puller for the flywheel. Waiting for a socket to be delivered for the spark plug. Got the bolts for the head cover off, but the head itself won't budge. Tried gently pursuading it with a bit of wood and no joy, don't want to go to hard and damage the metal
    Good point, I'd forgotten that. Do you recall what sprocket sizes you're running?

    I've actually been accumulating parts for a while now, so I have a dirt model shock as suggested and the frontend of a drz400. Bit more work but should be a nice upgrade.
    #8
  9. MotoPolo

    MotoPolo So many places, so little time Supporter

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    Portland OR
    That kind of drinking will drive you mad with ambition - sent me on a two year quest - subscribed:clap
    #9
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  10. MiteyF

    MiteyF Long timer

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    Jul 23, 2010
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    Location:
    Bay Area
    I've owned 2 DR350's, awesome bikes. Looks like this should be a good one!
    #10
  11. hellotimmutton

    hellotimmutton Been here awhile

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    Oct 24, 2016
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    Made some good progress today. Managed to finally get the head cover off by placing a flat bit of wood against it and whacking it with a hammer. After that, the cam and sprocket came out pretty easily. Not the best picture, but the cam journals are looking pretty good. seems like the kind of thing that should have bearings

    [​IMG]
    #11