Should I replace my air filters?

[Spargett]

Thanks guys. That link had some great priced air filters, 1/4 of what I've seen them around for. A million thanks.

[Spargett]

The air filters came today. But I noticed that right air filter is missing the nozzle to connect the air tube to. I spoke to Terry and Carole at RetroBikes and they said:

"When we had the filters made up, the right side was missing that little nozzle. Somehow, our engineer and the manufacturer decided that it wasn't needed. All of our filters are the same-nozzle on the left, none on the right."

Do you think this will pose any problems?

Here is a location to get perfect AM ones at a reasonable price. .................lm
<http://www.olypen.com/retro/>

[jleewebb]

there's a long thread on this in here somewhere...bottom line is using a tee to tie two breathers together, then to air filter, or just plugging the breather holes and nozzle on air filter as on later model. Others came up with more strung out solutions. You realize these go to crankcase breathers under carbs, not to overflow tubes on carbs. (This is a common mistake.) I'm enjoying your posts, keep it up! Lee

[e3steve]

Hey Scott, those nozzles were originally for the CB72's 'Power Jet' carbs'; not necessary for the 305 -- info courtesy of LM. Here's a little tutorial I posted a while back -- this time courtesy of the Honda shop manual: http://www.honda305.com/forums/viewtopic.php?t=3461 and a little on cold-starts: http://www.honda305.com/forums/viewtopic.php?t=3510

Ed has mentioned what to do with the inlet valve-guide breathers somewhere hereabouts, but Lee's tip of teeing and taking same to the left filter sort of makes sense to me -- although my breathers are just looped together (gotta do something about that!).

EDIT: found the topic - http://www.honda305.com/forums/viewtopic.php?t=3272

[Spargett]

The "T" solution seems most logical. The fact that the "engineer" decided that the nozzle wasn't needed on the right side just sounds absurd to me. This issue seems completely devoid of logic.

-Scott-

there's a long thread on this in here somewhere...bottom line is using a tee to tie two breathers together, then to air filter, or just plugging the breather holes and nozzle on air filter as on later model. Others came up with more strung out solutions. You realize these go to crankcase breathers under carbs, not to overflow tubes on carbs. (This is a common mistake.) I'm enjoying your posts, keep it up! Lee

[jleewebb]

My impression, I'm no expert, is that the vents function was to equalize atmospheric pressure inside and outside crankcase. Thus no great volume of air would need to go through them.

However many yen less it cost to make filter without spigot x how many bikes manufactured = more yen to bottom line. Later they apparently discovered vents weren't really needed and did away with them altogether on later models.

You may have to abandon logic and just go with the flow sometimes to get through your project with your sanity more or less intact. Good luck. Lee

[LOUD MOUSE]

Scott you are new to this. The early/original filters were designed/made for the CB72 (250) which was produced B4 the CB77 (305 and that bike used/had "power jet" carbs which had a special enriching system which required fresh clean air so HONDA installed small tubes from each carb to the corresponding air cleaners. That design also had the intake valve moisture removal passages which attached to a plastic "Y" and the one end of the "Y" had a tube which attached to a second (larger) tube on the right side air cleaner.So the right side air cleaner was issued with 2 tubes of different sizes. Along came the CB77 and the carbs didn't have the "power jet" system so HONDA installed RED soft rubber covers on the smaller tubes. The valve vent tube was attached to the larger tube same as the CB72. Some time in 1967 HONDA discontinued the valve vent system and at that time it seams all the air filters "CL72/77 included" were manufactured without any tubes on either filter and the head no longer had the "drilled/taped and threaded" locations. Some heads were issued with the casting area for the holes to be drilled and later the heads were issued with no evidence of the "vent system" at all existed. When I do a correct restoration I make a "large" tube with 1/4 in. brass tube soldered to a steel washer then installed on the right side filter with JB Weld and sprayed with KRYLON dull aluminum paint. If a person wants a rider and doesn't care about the bike having the vent tube being there (HONDA dropped it anyway) he/she can put 10 mm bolts in the holes in the head or install a rubber tube from one vent to the other. I see many restorations which have the tube/Y installed and the air cleaner end just hanging in the open and not attached to anything. Oh Well. ................lm

The "T" solution seems most logical. The fact that the "engineer" decided that the nozzle wasn't needed on the right side just sounds absurd to me. This issue seems completely devoid of logic.

-Scott-

there's a long thread on this in here somewhere...bottom line is using a tee to tie two breathers together, then to air filter, or just plugging the breather holes and nozzle on air filter as on later model. Others came up with more strung out solutions. You realize these go to crankcase breathers under carbs, not to overflow tubes on carbs. (This is a common mistake.) I'm enjoying your posts, keep it up! Lee