HS40 diaphragm carb

[copyman]

I have a regular bowl carb with slant adapter on bike and it runs fine but just realized original engine had diaphragm carb and wanted to keep this bike as original as possible.

Is there an aftermarket diaphragm carb sold for old 1970 HS40 engine? Or if anyone has good one to sell please PM me.


Thanks in advance

 

[nblakeh]

There's a diaphragm carb on eBay right now, however the choke and throttle butterfly linkage is wrong. probably was a replacement sometime in the past.

https://www.ebay.com/itm/3043406087...,osub=osub,crd=crd,segname=segname,chnl=mkcid

 

[mustangfrank]

I have a regular bowl carb with slant adapter on bike and it runs fine but just realized original engine had diaphragm carb and wanted to keep this bike as original as possible.

Is there an aftermarket diaphragm carb sold for old 1970 HS40 engine? Or if anyone has good one to sell please PM me.


Thanks in advance

If it's the original engine just plug the engine model number in at a parts house to at least get a part number to search for.

Good luck...might want to get one and just put it on a shelf to say "I have an original diaphragm carb"!

 

[copyman]

There's a diaphragm carb on eBay right now, however the choke and throttle butterfly linkage is wrong. probably was a replacement sometime in the past.

https://www.ebay.com/itm/304340608748?mkevt=1&mkpid=0&emsid=e11021.m43.l1120&mkcid=7&ch=osgood&euid=624ff819e80542e3be4dc2072d6d613b&bu=43091182748&ut=RU&osub=-1~1&crd=20220201032823&segname=11021&sojTags=ch=ch,bu=bu,ut=ut,osub=osub,crd=crd,segname=segname,chnl=mkcid

Thanks for the heads up. Is the wrong choke & butterfly a big deal or can they be replaced with original if available?

Are kits available to rebuild these carbs?

Thanks again

 

[creia]

Is this bike/build going to be a daily rider or garage queen? If the former I would stay with your bowl carb. I ask, because it has been my experience that the TEC bowl carbs perform better and are easier to tune that the diaphragm carbs- "your mileage may vary..." In addition, it will be a real challenge to even find a OEM TEC diaphragm carb with all of the correct (minibike) parts.
Michael

 

[nblakeh]

Thanks for the heads up. Is the wrong choke & butterfly a big deal or can they be replaced with original if available?

Are kits available to rebuild these carbs?

Thanks again

I believe you can change them out from a regular bowl carb although no guarantee. Somebody else on this forum might have a better answer. Rebuild kits are still available.