Author Topic: The lazy man's carb install (Read 17604 times)

wiskey · « **on:** June 12, 2012, 01:10:46 PM »

Hello, I know there are a lot of these "tips" on how to get the carbs back on. Well by accident I learned the easy way last night.

I have a 77 cb750k but i'm sure this is universal. (77&78 don't have the luxury of just buying new boots)

put a little bit of oil on the boot and get them on as much as you can by hand (I can get i think about 75%) still wont be enough to be free of air leaks but in my case the engine will start and idle but would die with any kind of throttle. leave off the air box it should still run.

Let the bike warm up for a few minutes, this lets your old hard boots warm up and more importantly make them pliable.

Cut the engine and go back and start pushing the carbs on. Much to my surprise they slid on the rest of the way with very little effort!

Let the motor do the work for you!

lucky · « **Reply #1 on:** June 13, 2012, 03:52:54 PM »

Here is another easy way.
Hold the carbs up in position.
Put two zip ties to the frame to hold the carbs up.

Next push the #4 carb into the boot as far as you can. Tighten the clamp.
Then go to the other side of the bike and push #1 carb into its boot. Tighten the clamp.

Gurp · « **Reply #2 on:** June 16, 2012, 03:39:20 AM »

I always put a dot of vasaline around the boots and then sat on the front tire reached around the engine grabbed 1 and 4 and leaned back and then slide right into place. a good freind showed me this.

72_350_FOUR · « **Reply #3 on:** July 05, 2012, 06:11:38 AM »

I found the carbs went on easy on my 350F, it's the darn black plastic chamber thats connects the air cleaner and the carbs that gave me fits. i found no easy way of getting it on. Any tips on that ?

seat cover man · « **Reply #4 on:** July 10, 2012, 09:06:25 PM »

i always just bring the intakes to a boil on the stove then slap em in order on the bike. u would be surprised with the expansion and it buys u like 3 minutes to get the carbs set in perfect place....im pretty sure industrial cafe taught me this trick...

DWS · « **Reply #5 on:** August 24, 2012, 07:51:18 PM »

hair dyer works good to to warm the boots up before you install

MoMo · « **Reply #6 on:** August 24, 2012, 08:00:44 PM »

Quote from: 72_350_FOUR on July 05, 2012, 06:11:38 AM

I found the carbs went on easy on my 350F, it's the darn black plastic chamber thats connects the air cleaner and the carbs that gave me fits. i found no easy way of getting it on. Any tips on that ?

The chamber has to be on before the carbs go on. I use C=clamps to hold it back against the frame and the carbs wil then have enough room to fit in. Others use tie downs. Search and you should get several other ideas but the clamps have always worked for me as long as the boots are soft (or have been softened in wintergreen/xylene...Larry

trueblue · « **Reply #7 on:** August 25, 2012, 02:23:27 AM »

On my 650Z, I sit astride the bike with it up on the centre stand, place my hands on the carbs with my knees behind my hands and my feet on the pegs. Push off the pegs with my feet and the carbs pop straight on. This technique may be a little difficult with the other SOHC4's because the 650Z's pegs are set further back than the factory spot on all the others I have seen.

LesterPiglet · « **Reply #8 on:** August 25, 2012, 04:41:17 AM »

I have it down to a fine art now. I put the carbs on, use my foot to push one side on the engine side, clamp it then do the other side then clamp. The rubbers from the airbox can be slipped in using some lube around the mating surfaces. My rubber boots are newish so quite flexible.

DWS · « **Reply #9 on:** September 28, 2012, 11:38:47 AM »

need parts fo my cb750 1978 f3 PD42A carbs. some doc saids its suppose to be PD42b and there not, whats up with that? bought the bike new in 1978

NewOldSchool · « **Reply #10 on:** September 28, 2012, 12:57:07 PM »

I boiled my boots in a large pot with 4 parts water and 1 part wintergreen oil for 45 minutes. Cleaned off all the old dirt and oil as well as made them soft and pliable like new.

I will install them with a bit of lube, tighten the clamps on the head and then put the carb rack on as best I can. The trick to get them really nice and snug is to take a ratchet strap and some rags. Wrap the strap around the head, cushion the fins and carbs with rags and slowly ratchet the carbs into place until they are seated.

Easy peasy.

mono · « **Reply #11 on:** October 25, 2012, 06:01:18 AM »

i usually just call my friend Bruce to come over and help me out. i don't know what he does to get them on, but when i get back from making a beer run, he's already got them on there, and his clothes are all torn up...

NewOldSchool · « **Reply #12 on:** October 25, 2012, 10:51:28 AM »

Quote from: mono on October 25, 2012, 06:01:18 AM

i usually just call my friend Bruce to come over and help me out. i don't know what he does to get them on, but when i get back from making a beer run, he's already got them on there, and his clothes are all torn up...

Where can I rent this "Bruce" you speak of?

mono · « **Reply #13 on:** October 25, 2012, 10:56:47 AM »

Quote from: NewOldSchool on October 25, 2012, 10:51:28 AM

Quote from: mono on October 25, 2012, 06:01:18 AM
i usually just call my friend Bruce to come over and help me out. i don't know what he does to get them on, but when i get back from making a beer run, he's already got them on there, and his clothes are all torn up...

Where can I rent this "Bruce" you speak of?

man, he's been hard to get ahold of lately since his accident at work. to bad too - he was a brillaint scientist. now he just wanders around doing odd jobs and helping strangers in need. maybe you'll run into him. just don't make him angry. you wouldn't like him when he's angry...

NewOldSchool · « **Reply #14 on:** October 25, 2012, 01:35:17 PM »

Duly noted.

disco · « **Reply #15 on:** November 02, 2012, 03:25:07 PM »

Use a ratchet strap & suitably sized piece of timber at back of carbs (for protecting carb throats). Loop the ratchet strap around the front of engine & tighten. Carbs pop right on without a struggle.

Delta869 · « **Reply #16 on:** July 11, 2017, 01:46:10 PM »

Quote from: trueblue on August 25, 2012, 02:23:27 AM

On my 650Z, I sit astride the bike with it up on the centre stand, place my hands on the carbs with my knees behind my hands and my feet on the pegs. Push off the pegs with my feet and the carbs pop straight on. This technique may be a little difficult with the other SOHC4's because the 650Z's pegs are set further back than the factory spot on all the others I have seen.

I just tried this method and it worked great! ... it's nice having a computer in the shop lol

Don R · « **Reply #17 on:** October 13, 2018, 08:12:15 PM »

I grease the boots and carbs with silicone grease, push them on far enough to get them started in the boots. Then place a piece of 2x4 on the carb inlets, insert a tire iron from above through the frame and pry against the 2x4 using the frame as a fulcrum. Make sure they are perfectly lined up and they usually pop right on. A rag will protect the paint on the frame. I broke a K0 carb bracket wrestling them before I tried this.

Redline it · « **Reply #18 on:** October 07, 2020, 05:03:20 PM »

Quote from: 72_350_FOUR on July 05, 2012, 06:11:38 AM

I found the carbs went on easy on my 350F, it's the darn black plastic chamber thats connects the air cleaner and the carbs that gave me fits. i found no easy way of getting it on. Any tips on that ?

from the rear with the air cleaner removed reach in with short hammer handle, or piece of wood , or the end of a crescent wrench and you can feel where to push around on the rubber mounts to the back side of the carb. it works for the inside 2 and 3 carbs. the outside goes on by just pushing the back sides by hand.

News:

Author Topic: The lazy man's carb install (Read 17604 times)