CB200 carb issues

[Johnwebley]

  I am have problems trying to get my 200 to run above 6K,

basically the air cleaners are unavailable,the originals were caked with dirt,although the bike ran OK,it was rich at high revs.

 I tried to sort it by ripping out the card/fibre board ,replaced by foam,then the problems started,

seem to run ok below 6K,and small throttle opening,.

 using standard needle,if I lift it one groove,it runs rich low down,

 so I increased the MJ in various stages to 110,from 88,,but will not run at full throttle above 6k,or rev past 6k,

 still seems lean,

 any ideas?

I know it has a long inlet tract,how does this effect it?
I suspect it is the pulses,and pressure waves to help fill the cylinder,

[K2-K6]

Long inlet tract is to harmonise at lower rpm to improve torque there.  Short inlet is usually focused at the screamer end of response.

That shouldn't have any affect on jetting from standard though as it obviously comes equipped in such a way.

Puzzled why it seems like it needs more fuel though.

Confident of ignition advance operating fully ? It'll not rev without that.

[Johnwebley]

the advance seems ok
,seems ok,opens easily when twisted by hand


will check when the sun next shines

[Oddjob]

Not exactly want you need to see John but.

https://classic-bikes.de/en/honda-luftfilter-satz-17200-354-005-3

Might solve the problem but bloody hell that's expensive.

[Johnwebley]

Not exactly want you need to see John but.

https://classic-bikes.de/en/honda-luftfilter-satz-17200-354-005-3

Might solve the problem but bloody hell that's expensive.

Bloody hell,glad I amsitting!!!

looks like around £100 each plus VAT !!!!

[Oddjob]

True. BUT, at least it's a pair and it could solve the problem and why oh why did Honda not make the filter seperate from the housing, that's just so stupid.

[Johnwebley]

agreed

 I wonder how many they sell nearly 50 years after original manufacture

[K2-K6]

agreed

 I wonder how many they sell nearly 50 years after original manufacture

You could try covering with stretchy fleece material John, just to assess what some level of resistance will give you. I've run this type of arrangement in really dusty conditions to cover the original filter material and prevent quick clogging (could be just pulled off and washed) which filtered pretty effectively.

[Moorey]

 Have you seen this John  https://www.hondatwins.net/threads/cb200-air-filter-refurb-query.1440/

[Johnwebley]

 Have you seen this John  https://www.hondatwins.net/threads/cb200-air-filter-refurb-query.1440/

  yes,tried that,purchased several lots of air filter foam,used a hot glue gun to assemble it,oiled the foam,

  not really worked,

 hence the desperation

[K2-K6]

Many of the car type are pleated paper that could be cut to size in replication.

Something like range rover 3.9 89/92 yrs is a non structured type of mostly paper that's only held in place by airbox structure and may be suitable to cut.

Or visiting local auto factors to see if you can find a suitable donor.

[K2-K6]

Looks like this

[ Guests cannot view attachments ]


Don't think they're expensive either.

[Johnwebley]

Not exactly want you need to see John but.

https://classic-bikes.de/en/honda-luftfilter-satz-17200-354-005-3

Might solve the problem but bloody hell that's expensive.

   OK,I have succumbed,
   cost so far not to bad,

  I expect to have to pay about £40 duty plus handling charge to DHL,

   jeez,

[Laverda Dave]

John, there was a feature in Classic Bike Guide a couple of months ago and written by Steve Cooper of VJMC fame. He is restoring a Yamaha 125 twin and needs new air filters that are unobtainable. He made his own filters and he runs through exactly how to do it. As long as you still have the end plates of your original filter it's quite easy to make. He gives details of the suppliers of the bits you need to make them. All very similar to the idea put forward by Nigel in his reply above.
Making them yourself will be a lot cheaper. You can get copies of CBG via the Mortons website.

[Johnwebley]

     Thanks Dave,

 I shall check that out ,

 My 125 Yam uses two foam  doughnuts over a centre intake  in an airbox,

  that works OK