Carburetor Boot Barbs vs In Carb Barbs for BS38 Carbs and Vacuum Petcocks

Just be aware that the "Prime" position runs off the reserve stand pipe, so now you won't have a "reserve" to fall back on. When you run out of gas, you will really be out of gas.

Since it sounds like you still have the two original petcocks, which are specific "left" and "right" units, you can do a manual petcock conversion. Details are here .....

http://en.650wiki.org/index.php/5.02.1_Vac_Petcock_Conversion
 
Thanks! I came across this page back when doing research as I rebuilt my petcocks in June. Had no idea what vac vs manual even meant at the time. Was just trying to follow guides and rebuild them to spec/working status again. Have forgotten about the entire site since then. After my trials and tribulations with the bike this summer, the notes in this link make complete sense now. I love the "ON" = anti-theft idea.

Bummed on the no reserve status of the vac petcocks as currently configured, but I don't have any anticipated long trips outside of the city with winter setting in and plan to keep the tank topped off between rides to hopefully prevent condensation/rust (ask me my thoughts on this in 2 months when I unexpectedly run out of fuel ;)). in the end I'll probably just go with Mike's manual replacements for the '78 when the time comes around, for simplicity.
 
So, exactly what's wrong with the replacement manifolds again? Are the vacuum nipples located in the wrong spot so they don't mate with the cut-outs in the tin covers, or are they just too long, or both?
 
A bit long and position doesn't align with the tin covers. Also, positioning of barb on right boot blocks against cap nut on right intake valve cover. Making it impossible to fit vacuum hose over barb or remove valve cover once installed. This seems to be the same problem among all aftermarket '78 barbed boot replacements I've found. I'm assuming they are all the same manufacturer at this point. Some retailers say to add a spacer between the engine and carb boot to fix the issue, but then the factory air filters don't have room to mate with the carburetors on the otherside. The boots are probably fine with the intension of suggested spacers and pod filters, but they aren't OEM matching parts.

Oddjob's solution shown previously in this thread of shortening the existing barb on the aftermarket boot, is about the best solution I've seen for the issue, but In practicality, I don't want to deal with risk of drilling/filling/potential for more air leak issues in the future and then also possibly have a diaphragm malfunction and flood the engine anyways.
 
I purchased carb manifolds from Niche Cycle. The barbs don't align with the shrouds and too close to the valve cover. I sent the an email and they said they would look into it. I sent another email and they said no other complaints have been received, I must be wrong. A few months later I went to purchase another item thru ebay from Niche Cycle and was informed that I am a blocked person and they refuse to sell to me. Talk about customer service, their product was NG and they blocked me.
tim.
 
Been using niche for mikuni brass, fast, right, n cheap, they charge actual first class parcel ie about $3 to ship the little stuff. :thumbsup:
 
Ya Gary---I also purchased other items in the past and was happy. But now they don't like me. lol
tim
 
Thats incredibly bizzarre. I had several calls and an email with them regarding this. I bought them direct and then returned for the same reason and informed them of the issue. I didnt even take them out of the plastic. I only measured them and knew they were same as Mike’s. The site listing is very vague and their customer service was pretty curt, all the way through to the RMA in the end. There however was one guy i got on the phone there who happens to specialize in classic bikes. He was very helpful and spent about 15 minutes on the phone trying to work through options with me. He even made measurements on the phone with me, basically almost confirming the issue without directly admitting the flaw. I bought anyways, just in case. Wish I remembered his name to ask for directly. None of them seemed to be aware that their product is incorrectly being billed as “modeled exactly after the original factory Yamaha XS650 carb holders”. Have not dealt with since. Who knows, maybe i’m banned too. Ha!
 
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