Base jetting vm28-418
Close
    
    
Page 1 of 3 123 LastLast
Results 1 to 10 of 26
Like Tree6Likes

Thread: Base jetting vm28-418

  1. #1
    Member Jd87's Avatar
    Join Date
    Aug 2014
    Posts
    34

    Base jetting vm28-418

    Can anyone tell me where to start for jetting a vm28-418 for my 02 tw200? I've searched and couldn't come up with anything. I want to order everything one one shot. And before I order are there any other direct replacement carbs for the tk to consider? Or is the vm-28 the best option? Below is the one I will be ordering.

    http://www.amazon.com/Mikuni-Series-.../dp/B000GZO5EG

  2. #2
    Senior Member jbfla's Avatar
    Join Date
    Jul 2010
    Location
    FL. GA, NC
    Posts
    2,392
    Sebastian (MacBig) is the only one that I am aware of that is using the VM28, and his bike is not a stock TW200.

    He has posted that it is not a easy carb to get properly tuned.

    Perhaps he will soon post about it.

    An alternative carb is one of the Chinese copies of of the Mikuni VM24/26, listed on eBay as a BW200 carb.

    The carb will work (I have tried one on my TW). However, you will need to modify the carb screw-on top, where the throttle cable connects.

    Or better yet, make a custom throttle cable, so you don't need to mod the carb top.

    Either way you will need a different cable, and perhaps a different throttle control. The stock throttle cables are in a push-pull configuration, and the VM28 is a single pull cable, which has a different lug on the carb end.

    The Chinese carb is also shorter from front to back so the air box boot is too short. Another forum member has solved the problem using duct tape.

    If you bike is a pre-2001, you will also need a separate start/kill switch.

    Jb
    2018 Triumph Street Twin..............2016 CB500F
    2014 XT250 ..................................2008 H-D Softail Deluxe
    2008 SV 650..................................2007 DR 650..

  3. #3
    Senior Member Fred's Avatar
    Join Date
    Dec 2011
    Location
    Turtle Wrangling the Sierras
    Posts
    18,587
    Have you searched archives here, specifically those of PalmStateCrawler and MR.Bracket? They have both been down the road of all that is involved with the care and feeding of the Mikuni VM28-418 in a TW application and have reported here in depth. Somewhere in those depths I seem to recall baseline jetting numbers. I seem to recall a bit of modifications were required and the resulting performance was never good enough to sweep the world by storm.
    To bad as I drooled over idea of crisper throttle response of the pumper carb option but Mr.Bracket couldn't get sufficient performance out of that one either it to make a conversion kit for TWs.
    You could start here, although I think PalmSrateCrawler sold his bike and moved on.Jets for mikuni tm28-1 and vm28 for sale
    2003 TW200 "Betty Boop"
    2006 TW200 "Nibbler", a.k.a. “Mr.Gizmo"
    Hidden Content All Things Considered I’ld Rather Be Motorcycling

  4. Remove Advertisements
    TW200Forum.com
    Advertisements
     

  5. #4
    Senior Member jbfla's Avatar
    Join Date
    Jul 2010
    Location
    FL. GA, NC
    Posts
    2,392
    Quote Originally Posted by Fred View Post
    Have you searched archives here, specifically those of PalmStateCrawler and MR.Bracket? They have both been down the road of all that is involved with the care and feeding of the Mikuni VM28-418 in a TW application and have reported here in depth. Somewhere in those depths I seem to recall baseline jetting numbers. I seem to recall a bit of modifications were required and the resulting performance was never good enough to sweep the world by storm.
    To bad as I drooled over idea of crisper throttle response of the pumper carb option but Mr.Bracket couldn't get sufficient performance out of that one either it to make a conversion kit for TWs.
    You could start here, although I think PalmSrateCrawler sold his bike and moved on.Jets for mikuni tm28-1 and vm28 for sale
    Fred, didn't Mr. Bracket and Palm State Crawler use the TM, a pumper carb?

    The VM is not a pumper carb.

    Jb
    2018 Triumph Street Twin..............2016 CB500F
    2014 XT250 ..................................2008 H-D Softail Deluxe
    2008 SV 650..................................2007 DR 650..

  6. #5
    Senior Member jbfla's Avatar
    Join Date
    Jul 2010
    Location
    FL. GA, NC
    Posts
    2,392
    Well, there may be a bit of confusion on my part.

    I checked the Mikuni catalog, and the VM carbs are all listed as "round slide" carbs. All except for the VM28-418 which is listed along with the "flat side" TM carbs....?

    ...waiting for MacBig or Mr. Bracket to clarify.

    jb
    2018 Triumph Street Twin..............2016 CB500F
    2014 XT250 ..................................2008 H-D Softail Deluxe
    2008 SV 650..................................2007 DR 650..

  7. #6
    Senior Member Fred's Avatar
    Join Date
    Dec 2011
    Location
    Turtle Wrangling the Sierras
    Posts
    18,587
    Escuse me, I was referring to the TM28-1 not the VM28-418 ,as the Mikuni pumper that Mr.Bracket and PalmState Crawler also experimented with unsuccessfully; discussions for both conversions were part of the referenced postings by both authors if I recall correctly. Either way neither Mikuni was deemed a perfect upgrade for everyday use.
    Dryden-Tdub likes this.
    2003 TW200 "Betty Boop"
    2006 TW200 "Nibbler", a.k.a. “Mr.Gizmo"
    Hidden Content All Things Considered I’ld Rather Be Motorcycling

  8. #7
    Senior Member Dryden-Tdub's Avatar
    Join Date
    Apr 2014
    Location
    Dryden NY
    Posts
    6,336
    Quote Originally Posted by Fred View Post
    Escuse me, I was referring to the TM28-1 not the VM28-418 ,as the Mikuni pumper that Mr.Bracket and PalmState Crawler also experimented with unsuccessfully; discussions for both conversions were part of the referenced postings by both authors if I recall correctly. Either way neither Mikuni was deemed a perfect upgrade for everyday use.
    Fred, you are getting old and forgetful. How could you recall so poorly!?


    Oh dear. I have been bad again....... Who will you have punish me this time Fred?

    I will be waiting patiently with a glass of wine and some lotion



    Tom
    It won't be greed which destroys America. It will be envy.

    Man who runs in front of motorcycle gets tired. Man who runs behind motorcycle gets exhausted.

  9. #8
    Senior Member jbfla's Avatar
    Join Date
    Jul 2010
    Location
    FL. GA, NC
    Posts
    2,392
    Quote Originally Posted by Fred View Post
    Escuse me, I was referring to the TM28-1 not the VM28-418 ,as the Mikuni pumper that Mr.Bracket and PalmState Crawler also experimented with unsuccessfully; discussions for both conversions were part of the referenced postings by both authors if I recall correctly. Either way neither Mikuni was deemed a perfect upgrade for everyday use.
    Here's the carb Mr. B used:

    https://tw200forum.com/forum/performa...html#post56577

    Apparently, the VM28 is part of the TM series of the Mikuni flat slide carbs...really confusing to me.

    The link provided by the JD87 shows the carb listed as both a TM and a VM.

    IMO.., a better choice for for a stock TW200 would be the Mikuni VM24 or VM26 round slide carb.

    Those are the ones that the Chinese clones are copied from, and we know the Chinese carb will work, with modifications to the throttle and cable, and the boot to the air box.

    jb
    Last edited by jbfla; 02-22-2015 at 10:20 PM.
    2018 Triumph Street Twin..............2016 CB500F
    2014 XT250 ..................................2008 H-D Softail Deluxe
    2008 SV 650..................................2007 DR 650..

  10. #9
    Senior Member jbfla's Avatar
    Join Date
    Jul 2010
    Location
    FL. GA, NC
    Posts
    2,392
    Interesting enough is one of the Amazon reviews on the OP's link:

    Amazon.com: BIGFOOT's review of Mikuni TM Series Flat Slide Carburetor (VM...

    ...wonder how Bigfoot got it to work.

    jb
    2018 Triumph Street Twin..............2016 CB500F
    2014 XT250 ..................................2008 H-D Softail Deluxe
    2008 SV 650..................................2007 DR 650..

  11. #10
    Senior Member Fred's Avatar
    Join Date
    Dec 2011
    Location
    Turtle Wrangling the Sierras
    Posts
    18,587
    I got really confused with various posts referring to two different carbs and designations, sorry. But to quote MrBracket in his build post #390
    "Yes, it's a Mikuni TM28 (aka:VM28-418) It is a 28mm Flat slide carb that is very similar to the ones found on 1980-1990's Suzuki RM80's"
    Yet PalmStateCrawler's classified add seems to depict and refer to two different carburetors. Odd. Jets for mikuni tm28-1 and vm28 for sale
    I'll back out now and let Original Posters clarify things, was just trying to help.
    If indeed Jd's carb is the same as MrBrackets as depicted in posts around #390 he might find the jetting answers he seeks starting around post #340.
    Remember carb says "Not For Aircraft" so be careful how high you get that hot rodded TW flying after she's all jetted up.


    P.S. BIGFOOT could be contacted via his Amazon.com sales site for details
    Last edited by Fred; 02-22-2015 at 11:50 PM.
    2003 TW200 "Betty Boop"
    2006 TW200 "Nibbler", a.k.a. “Mr.Gizmo"
    Hidden Content All Things Considered I’ld Rather Be Motorcycling

Page 1 of 3 123 LastLast

Sponosred Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Re-jetting
    By r_marsh in forum Performance and Customization
    Replies: 1
    Last Post: 06-05-2014, 11:13 AM
  2. Jets for mikuni tm28-1 and vm28 for sale
    By PalmStateCrawler in forum TW200 Classifieds
    Replies: 0
    Last Post: 10-16-2013, 12:31 AM
  3. Jetting for maintenance
    By Adam-n-nevada in forum Technical Help
    Replies: 1
    Last Post: 11-02-2012, 07:53 PM
  4. Jetting Tip - Too rich
    By len in forum Performance and Customization
    Replies: 2
    Last Post: 08-08-2012, 09:55 PM
  5. Jetting for 10k feet
    By -Jake- in forum Performance and Customization
    Replies: 7
    Last Post: 08-07-2012, 05:04 PM

Search tags for this page

chinese clone tw200
,
mikuni tm28
,
mikuni tm28 clone
,

mikuni vm28

,
mikuni vm28-418
,
mikuni vm28-418 tw200
,
teikei tk round slide tw200
,
tw200 mikuni
,
tw200 mikuni carb vm28
,
tw200 mikuni vm26 swap
,
tw200 mikuni vm28-418 upgrade
,
tw200 with mikuni tm28
Click on a term to search for related topics.