Just a quick question

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crazylemur

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Is it recommended to replace the carb intake manifolds? mine are pretty worn looking, and the rubber diaphrams between the air filter and the carbs look like they may have some cracks? I'm doing my first carb cleaning and I'm sitting around waiting on new pilot jets (had to use a screw extractor on both), the carbs didn't look too dirty on the inside btw
 
If yours are cracked, I would replace them. Eventually, they will crack all the way through and you will get a lean condition. The rubber boots from the carbs to the filters are less important, but if they are bad, they can throw off settings and let unfiltered air in.

As a matter of terminology, "manifold" means an arrangement of pipes or passages with many going into one or one going into many. In a car or bike with less carbs than cylinders, there is an "intake manifold". When you have 2 carbs and 2 cylinders, you have carb holders or intake boots....but it really doesn't matter that much. I've just seen that term used a lot lately and had a conversation with a guy with a CB750 yesterday who used the same term.
 
I think I'm inclined to agree that while you're doing work on the carbs,you might as well fix or replace what you can see is bad. All it takes is a small tear in the boot between the carb and filter and you could get a lot of dust and grit into the carb,and chamber,wearing out the rings and bore. A leak between the carb and the head will cause a lot of problems,such as lean condition,and what I described for the rings and bore. lha
 
Thanks a ton guys, it seems like this is going to be a not so quick question haha. I'm also wanting to replace the air filters as mine are looking pretty worn, they're not falling apart yet but I feel like I might as well get everything working top notch now. This is a bit of a noob question but whats the difference between pods and UNI's? And where can I even buy these from? Theres lots of threads about them, but most have an assume knowledge I don't have. I saw threads where people have went and bought their own filter material, are these UNIs? Also from what I've read the carbs will have to be rejetted so this is a good time to change out mufflers right? I'm staying with the 2 into 2, does anyone have any experience with these or is there anything else that comes highly recommended?

http://www.dimecitycycles.com/vinta...st-parts-12-inch-shorty-muffler-80-03310.html

Also as far as ordering new jets, what all should I get? Waiting on parts really sucks so do you think I'll be alright getting a 145 and 147.5 for the main and just a 45 for the pilot jet?

Thanks in advance!
 
The intake boots on mine have a few cracks but must not be leaking or my mechanic would have replaced them. From what I can see, it looks like a bit of JB Weld or the like would solve the problem. My boot between the carbs and filters had a couple very minor cracks near the clamps but they weren't through. From what I could see on E-Bay, the ones for sale were worse than mine. I'd like to find a NOS to replace mine if it begins to leak. The guy that was fixing my bike was going to use Uni's with the foam covers but I liked the looks of the K&N look-a-like Emgo's better. Now though, I think the Uni's with red foam covers would look great with my red tank and might change them.
 
Alright so I went ahead and ordered new boots. Now I'm wondering does anyone use these? what kind of jet adjustments could I expect with these
On the site it says a 25% increase in jet size, that sounds like a lot...
http://www.oldbikebarn.com/Chrome-Round-Pod-Air-Filter-54mm?sc=2&category=2109

Also could anyone post give me some links to where to buy air filters, partsnmore is sold out of the ones that'll fit in the stock air box, and most of the other sites are lacking 54mm ones
 
happy61 said:
The intake boots on mine have a few cracks but must not be leaking or my mechanic would have replaced them. From what I can see, it looks like a bit of JB Weld or the like would solve the problem. My boot between the carbs and filters had a couple very minor cracks near the clamps but they weren't through. From what I could see on E-Bay, the ones for sale were worse than mine. I'd like to find a NOS to replace mine if it begins to leak. The guy that was fixing my bike was going to use Uni's with the foam covers but I liked the looks of the K&N look-a-like Emgo's better. Now though, I think the Uni's with red foam covers would look great with my red tank and might change them.
Click to expand...
J.B. weld is for metal,not for rubber.I had some cracks on the rubber carb to head transitions on my dirt bike,and fixed it with liquid electrical tape,a couple of layers,but they're not available as it's a '75 model.I have a UNI sock air filter on it as the air boots aren't available either.My cracks were minor,and I don't think they were leaking,but didn't want to risk it.Evidently the boots for the xs machines are available,so you'd be better off getting new ones. I adjusted the needle jet on my bike['75 Dt400]and it works well,but you'd just have to see how yours runs to be able to determine how much to change it to get it right. lha
 
crazylemur said:
Thanks a ton guys, it seems like this is going to be a not so quick question haha. I'm also wanting to replace the air filters as mine are looking pretty worn, they're not falling apart yet but I feel like I might as well get everything working top notch now. This is a bit of a noob question but whats the difference between pods and UNI's? And where can I even buy these from? Theres lots of threads about them, but most have an assume knowledge I don't have. I saw threads where people have went and bought their own filter material, are these UNIs? Also from what I've read the carbs will have to be rejetted so this is a good time to change out mufflers right? I'm staying with the 2 into 2, does anyone have any experience with these or is there anything else that comes highly recommended?

http://www.dimecitycycles.com/vinta...st-parts-12-inch-shorty-muffler-80-03310.html

Also as far as ordering new jets, what all should I get? Waiting on parts really sucks so do you think I'll be alright getting a 145 and 147.5 for the main and just a 45 for the pilot jet?

Thanks in advance!
Click to expand...

UNI is a brand of pod filters.The ones that I have on my bikes,which were used because the stock stuff was hard and broken,are green 6" pod filters and oiled. lha
 
My JB Weld says for metal, wood, ceramic, pvc and numerous other materials. I repaired my rubber fish pond with it below the waterline and have never had a problem with leakage. The stuff is really pretty amazing. The 6" UNI's might be just the ticket since if used on the end of the rubber boots they would cover up the battery area somewhat.
 
I got mine at cheap cycle parts.com.They aren't hard to find,but I believe I'd use them like Drewpy says,with the rubber boots instead of directly on the carbs.The major advantage to pods is because they are washable,I just soak them in soapy water a few minutes,agitate,blow them out from the inside with water,dry,oil,install. lha
 
So what is the size needed for the early, 77-78 carbs? I put 48mm on and they seem too small. Is the correct size 51mm or 54mm? Has anyone used the UNI's with the 15 degree angle? Seems like it might get the filter away from the battery holder a bit. I took mine off the carbs and put them on the boot as Drewpy did. Looks way better IMO, and you can use the existing breather configuration.
 

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