Sanjohsaki the Build

Discussion in 'Some Assembly Required' started by sanjoh, Mar 25, 2010.

  1. sanjoh

    sanjoh Long timer

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    Wheel size follows what kind of riding you plan on.

    The motor/gearbox is the highlight of the bike. I will install a 48t rear sprocket so 1st gear is more in the power.

    You will need a lathe or a friend with one:)
    #61
  2. Whereabouts

    Whereabouts Been here awhile

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    Very nice build! When can I expect to see a Sanjohsaki dealer in my area? Their product line is rather small but very interesting.

    I have a couple of questions for you if you don't mind. First, unless I'm wrong, you are reducing trail when you swap to a leading axle fork. Did this have any adverse effects on handling or is this being compensated for by having the bike raised more in the front than in the back? Did you sit down and calculate the suspension geometry you wanted to attain or did you just do it by feel? If you did have a target would you mind sharing it?

    Secondly, I'm curious what you've done with your footpegs following the break. Did you replace with stock parts or work out a way to drop the pegs while you were at it? Any pics?

    Thanks for sharing the fruits of your innovation with us.
    #62
  3. sanjoh

    sanjoh Long timer

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    Your welcome.

    The main measurement I was interested in was the rake. I didn't have any control over the trail, without big changes, it is what it is. The rake is between 25 & 26 degrees.

    I had modified (grinder) the previous footpeg mounts to fit the buell pegs, I bought another set of peg mounts with pegs for $16, added the vario MSW adjustable pegs and all seems ok, just stay away from the big air:D. I haven't modified the peg mounts as I now have them holding my luggage and muffler.

    The bike retains a lot of it's sportbike handling, I'm currently on a multiweek trip, just rode the Cherohala and Dragon. Damn close to sportbike performance (sans luggage) with the Shinko 700s.

    [​IMG]
    #63
  4. mtothef

    mtothef perpetually furrowed brow

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    one thing to remeber when playing around with offset, rake and trail and such: for a given offset/rake/head angle, changing wheel diameters will have an effect on trail. decreasing wheel diameter will reduce effective trail, while increasing wheel diameter will increase effective trail.

    i haven't crunched the numbers on that to verify exactly how much change is effected, but going from a 17 to a 21 front wheel then slapping an offset axle front fork on there actually makes some sense. also explains why certain mx bikes converted to supermoto with no change in fork offset or geometry tend to be a bit squirrely on the brakes...
    #64
  5. Whereabouts

    Whereabouts Been here awhile

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    Thanks for the feedback, that's great to hear. And yes, it makes sense that changing the front wheel diameter and also presumably raising the front suspension a bit more than the rear would help offset the loss in trail. I'm glad to hear that you didn't have to be a super-engineer to build a great handling bike.

    What did you cook up for a windscreen (in that last pic)?
    #65
  6. sanjoh

    sanjoh Long timer

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    Look for fly n cycle on ebay. $59, works great, they did however ship a replacement as the first one was cracked.
    #66
  7. dentvet

    dentvet Long timer

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    in comparison to regular dirt bike ergonomics, the pegs aren't all that high, they are just too far back away from the grips, like 5-6 inches. this causes me to be tilted forward when standing, having to lean across to the bars.

    i can see how a riser would help some but either the bars have to be moved rearward or the pegs have to be moved forward. i see that rox makes a pivoting 6 inch bar riser

    moving the pegs forward looks difficult as the shifter and linkage presents a serious problem, more so than the brake setup on the right side.

    here's mine so far, its kind of limbo until i get the inspection out of the way. i have a yamaha wr roller that i might scavenge for the frankenbike mods. so many options but i might like it as-is...

    [​IMG]
    #67
  8. sanjoh

    sanjoh Long timer

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    Ideally the peg would be up around the swingarm pivot for front to back location, height is another discussion.
    #68
  9. BlueLghtning

    BlueLghtning Riding is my passion

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    I think I saw your bike at the little cafe just outside Iron Horse Lodge last weekend. It would have been Friday, Sept 10th. I saw the Ninja 650 dirt biking thing and turned around to go take some pics. I was on an orange Vstrom 650 loaded down. I was going to come in and talk to you, but my wife and father were waiting on me down the road. (Unfortunately, I didn't realize till I got home, but my camera had started way over exposing all my pics. (LCD broken) So I didn't get any pics worth sharing and can't tell if its your bike or not, but looked like it.

    I'm really thinking I want to do one of these. My wife had owned an 08 Ninja 650R that we had bought salvaged and fixed it up for her that was her touring bike before her current F650GS. That was a great bike. We ended up selling it though, but it would have been a great platform. I've also owned a few 1st gen SV650's. I can't decide which bike would make the better platform to start with. The Ninja 650R is FI, but I could go with a 2nd gen SV, but I think the 650R's are cheaper to pick up.

    My hesitation with the 650R is the under bike exhaust (but you found a pretty good solution), and the weird rear shock. The SV650 (like the DL650 has the front oil filter out there, but bash plates are pretty easy to find for it.
    #69
  10. sanjoh

    sanjoh Long timer

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    Yep that was me. I was on looong conference call otherwise I would have come out to say hi. It is a do it all bike, the ninjas are so inexpensive to begin with, I just bought the wife a brand new 09 er6n for<4k. Just turned over 17k miles riding in Missouri today. SE Missouri is sweet, great twisties, gravel, dirt, best of the temp was < 80:clap great change from FL.
    #70
  11. BlueLghtning

    BlueLghtning Riding is my passion

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    Awesome, I figured it was you.

    Yeah, the Ninja 650R's are dirt cheap and such great engines. We bought my wife's 08 salvaged with 1k miles on it for pretty cheap (all minor cosmetic damage). She put 17k miles on it before we sold it for $2500 and that ended up being pretty cheap as my phone blew up from the calls. I thought the rebuilt title was going to hold people back, but they jumped all over it.

    I owned a KLR for awhile and I really wasn't a fan of it. I think I'd much enjoy turning a bike like this into a fun DS.

    The Vstrom is my ideal bike for general riding, but I don't like to get it in too serious off road and the 17/19 tires don't have the tire options a 18/21 would. I think the Ninja 650R (or SV) turned DS bike would make a nice dual sport that is way lighter then a Vstrom, more capable off road, but can easily eat the miles up in between too.
    #71
  12. dentvet

    dentvet Long timer

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    still waiting for a stupid state inspection! in the mean time i had a random question.

    when (not if) i take my bike into the national forest, will i get hassled for a spark arrestor? does the stock ninja muffler have a spark arrestor? do most street bikes (gsxr)? mine has a 2 brothers exhaust that is more like "2 loud" and probably doesn't have a usfs approved sa.

    there is a local ohv place in the national forest that is patrolled
    #72
  13. sanjoh

    sanjoh Long timer

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    You may get hassled for the spark arrester. I put a screen over the end cap on my GSXR 1k muffler.
    #73
  14. sanjoh

    sanjoh Long timer

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    I actually installed the swmotech crash bars today:clap

    and measured for a shock. Looks like about 10.4" of available travel, although the swingarm is at an extreme angle.

    Low ride er
    [​IMG]

    Gettin High
    [​IMG]

    The swingam will bottom on the stock muffler, if that's gone then it will bottom on the muffler hanger which is now 1/2 original size.
    [​IMG]
    #74
  15. jdrocks

    jdrocks Gravel Runner

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    crash bars? is that what they're for?

    did you happen to see my review of those folding mirrors?
    #75
  16. sanjoh

    sanjoh Long timer

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    Let's hope not but they are sturdy

    Must have missed it, got a link?
    #76
  17. taco250

    taco250 wannabe adventurer

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    Just finished reading your build story. I'm really impressed. I don't like your muffler but that's a subjective thing. Recently, I was thinking of putting a EX250 motor in my XRL just for more mpg and street performance. I think your dirt Ninja is a better idea. Congrats!:clap
    #77
  18. BRE

    BRE Been here awhile Supporter

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    Wow, that is an extreme angle on the swingarm. The KLR has 7.3" of rear travel, the GS800 8.5, the KTM 990 8.3, I would think between 7.5 and 8.5 would be the sweet spot.
    #78
  19. jdrocks

    jdrocks Gravel Runner

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    #79
  20. sanjoh

    sanjoh Long timer

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    Hey Taco build the ex250 into a dualsport. The xr is already porky and would be underwhelming with the 250 motor.

    JD thanks for the heads up. I've had nothing but good luck with mine. I did break a mirror in one but the mounts have held up fine after several drops although I try to position them to be inside the handlebars in a fall.
    #80