Rotten Intake Boots: Time for them to go walkin'

[OdysseusXS]

Good morning everybody, went for a ride last night out to my brother's place. When I got there we set about swapping out a vacum line from the left hand intake boot. PO had bodgied it up and used what we thought was two pieces of vac line joined by what we thought was some sort of 'joiner'. It was in fact two bits of vac line held together by the end of a woodscrew that had it's head cut off. The thread was used to simultaneously 'join' the two bits of shite vac line/ AND block off the intake barb. As we began dealing with this the vac barb tore out of the boot and upon closer inspection the entire point where the barb into the boot was completely cracked crumbling and rotted. Aussie ingenuity prevailed and hi-temp silicone solved the problem (temporarily). I have read a bit about MIKESXS on this forum and to be honest I'm hesitant to buy the intake boots he has/had on offer. Fleabay offers supposed japanese made boots for my '82 sj/k? for about forty bucks plus postage, the pics look ok. Where's the best place to get 'em? (Sidenote: the fuel tap (aussies don't say 'petcock' it sounds like a dangerous pet) is no longer vacuum controlled, it works in an always on state, don't know why but it does not leak fuel, so for now I'm leaving it alone. Do I only need the vacuum barb for carb balancing? Any feedback gratefully accepted.

 

[ippytattoo]

If your fuel tap is a non vacuum type then yes the vacuum barbs are only for carb sync. If you are not worried about syncing the carbs using a manometer or vacuum gauges then I would suggest looking at JBM Industries for new boots without the vacuum barbs.

 

[OdysseusXS]

Thanks ippytattoo, want to keep the vac barbs if possible. Don't know much about syncing carbs but I assume it's pretty important as part of an overall tune.

 

[ippytattoo]

650central.com sells some of the boots for the 80-84 bs34's with barbs. I can't say anything about them as I have never used them. May be worth a shot though.

 

[xjwmx]

aussies don't say 'petcock' it sounds like a dangerous pet) is no longer vacuum controlled, it works in an always on state, don't know why but it does not leak fuel, so for now I'm leaving it alone.

I gutted my pet rooster. It was too much trouble. Then I glued his halves back together and put a red and black lawnmower valve in the line so I could turn the gas off. Phase two on your rooster after it won't turn off is it will leak around the diaphragm and piss gasoline on your motor. Eventually. Potential glorious death blaze scenario for an ending.

 

[OdysseusXS]

I will be looking into swapping the pet cockerel (vac controlled) to a manual variety, which I suspect will be far less dangerous Thanks xjwmx. BTW, where did your avatar shot come from, it looks strangely familiar, but something in the back of my head is saying that it came from a film, "Easyrider"?

 

[xjwmx]

it looks strangely familiar

Just an average guy who happens to have a direct connection to the subconscious. Meet 'em every day.

 

[OdysseusXS]

Reasonably Gothic handlebar ornament, I think my connection to the subconscious is intermittent at best

 

[Growl]

I recently bought some carb boots (with barbs) from Michael Mercury Morse (650 Central)

They are made in Japan, which is promising. They look good...

 

[OdysseusXS]

Thanks for the heads up growl, I'll check them out. I've read good things about the MMM.

 

[gggGary]

I saw those ebay "Japanese" intakes, I think that is a new development. Someone will have to be the guinea pig.....
Petcock rebuilding is not rocket science but it does require patience and attention to detail.
Some many? rebuild kits fail in not having the correct seal for the perimeter of the selector disk......

 

[xjwmx]

Petcock rebuilding is not rocket science but it does require patience and attention to detail.

I noticed once this place sells the diaphragm only, which is probably all you need, at least if it's a second rebuild. What I did to mine was in an emergency situation.

http://www.jetsrus.com/individual_parts/KL_18_6633.html

My first rebuild developed a hole in the diaphragm which let it leak out the little channel in the plastic part. The second time I thought the same thing was happening, but really the diaphragm was leaking around the edge because it had dried out and thinned there. No hole. If I'd put a good surface on the flanges, then that rebuild might still be working. There was a good vac rebuild article, prob. in the Tech section now.

 

[650Skull]

Here is the link to the Vacuum petcock rebuild thread

The main complaint with Mikes Inlet manifolds was that ethanol blended fuel was eating them up. His other rubber products have a bad rep but if you don't use the blended fuel they may be ok.

Take the vacuum plugs out of the old inlets and drill a hole and fit them to the JBM ones

 

[XSLeo]

On a vacuum petcock, the positions are Prime, On, Res. In normal operation you leave the petcock in on or reserve. No fuel will flow until the engine starts. If the bike has set and the fuel in the carbs has departed to where ever fuel goes you use the Prime position, this bypasses the vacuum valve and lets fuel flow. Once the carbs fill and you start the bike, turn to on or reserve.
If your vacuum fails as yours has by being blocked with the screw, just use prime to run the bike and on when stopped.
On the carb boots, there are some out there branded Tour Max. They are also sold under the manufactures name, I just don't recall it right now. These are good carb holders, ethanol resistant and are made to stock specs and can use the steel cage that fits the stock carb holders.
The JBM Industries are a good product, ethanol resistant but not made to stock specs and the stock steel cage won't fit. These carb holders can crack unless the carbs have the support of the stock air boxes or an added brace to support the weight of the heavy stock carbs.
Leo