Carb question

Hello,
I'm a new to bikes. Just picked up a 82 650 xj Maxum. Came with a 80 650 parts bike.

Bike runs and drives good. Problem is you have to use starting fluid to cold start it. Once it's warm it fires right up.

Previous owner started a bobber build and lost interest. He installed the pod filters and put the carbs from the 80 on the 82. Exhaust was gone when he bought it. So he installed the straight pipes.

I have a few questions.
-Will the carbs work off of the 80? If not what do I need to change to make it work?
-i read thru the hour of learning article and it said about changing the jets due to the pods and open exhaust . Should I put bigger jets in when I clean the carbs or should I wait?


Any suggestions are welcome. Thanks for the help in advance.

 

You should put a factory airbox back on. You should also clean the enrichment wells in the float bowls.

The carbs from teh '80 are the same as on the '82, but some of the jets will need to be swapped from the '82 carbs into the '80 carbs. Honestly you probably won't need to do that since the '82 carbs are working. The enrichment circuits likely just need to be cleaned.


If you want to keep the pods....well.....give us a pic of the business end of each sparkplug (numbered by which cylinder they are from). Also read the link in my signature, particularly the fifth page.

 

nice paint scheme, real white walls or painted?

link for carb specs
http://xjbikes.wikidot.com/carb-specs
at bottom of link on specs it tells you where to start for your mods

XJ650 Models:

Years & Models: 1980-1 XJ650 Maxim, Midnight Maxim, and XJ650RJ Seca USA models
Carb Manufacturer: Hitachi
Carb Series: HSC32
Carb Model ID: 4H700
Main FUEL Jet Size: #110
Pilot FUEL Jet Size: #40
Main AIR Jet Size: #50
Pilot AIR Jet Size: #195
AIR COMPENSATOR Jet Size: #36
Starter FUEL Jet Size: #40 (non-replaceable, in float bowl)
Main jet NEEDLE ID: #Y-10
Main needle JET Size: #3.2mm (the main needle JET is also known as the "power valve" or "emulsion tube").
Fuel Level in float bowls: 3mm +/- 1mm (.118" +/- .039")
Idle RPM's: 1,050 rpms

Years & Models: 1982-3 XJ650 Maxim USA models
Carb Manufacturer: Hitachi
Carb Series: HSC32
Carb Model ID: 5N800
Main FUEL Jet Size: #110
Pilot FUEL Jet Size: #40
Main AIR Jet Size: #50
Pilot AIR Jet Size: #205
AIR COMPENSATOR Jet Size: #36
Starter FUEL Jet Size: #40 (non-replaceable, in float bowl)
Main jet NEEDLE ID: #Y-10
Main needle JET Size: #3.2mm (the main needle JET is also known as the "power valve" or "emulsion tube").
Fuel Level in float bowls: 3mm +/- 1mm (.118" +/- .039")
Idle RPM's: 1,050 rpms

and some reading on carb jet tuning
http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html

 

If enrichment cicuits are good then check/fix valve clearances - I'm convinced this can also contribute to poor starting. I'd also be inclined to replace those steel bars with something a bit springy-er - like shock absorbers.

 

Thanks for all the replies.

When I get home I'll take a picture of the plugs to see what they look like. The pods are there so if I can make them work I will, if not I'll change them.

They are white walls. I can't take credit for the bike scheme. Previous owner did all that. Thinking about cleaning things up and continue his idea.

It looks like I might need some jets. If I have time this weekend I'll try and check the valves.

The parts bike has shocks on it. So I'm probably going to shorten the springs some. I'm 5'7'' so the shorter the better.

 

make the time to check the valves , you are wasting your time trying to tune it if step 1 is not done

AIRHEAD VALVE ADJUSTMENT with Pics

AIRHEAD VALVE ADJUSTMENT Part 2: The Tool vs. ZipTie -w/pics

 

Here's a pic of the plugs. They don't look that old. Half the insulator looks almost purple and the other half is white.

 

If you drop the rear more than 2" from the stock height, the u-joint will want to bind, and eventually become an ex-u-joint.

 

Those plugs look oily. Wipe a finger across each one. How to they feel?

 

This is plug 4.

 

The previous owner said he put 2 cycle gas in it by accident before. It has a slight oil feel.

 

That would explain the coloration and feel.

 

I have no idea how low it's dropped now. Another thing for the list.

If I have time I'll pick up some new plugs this week and flush the tank .

Bike isn't road legal yet so road testing isn't much of an option.

 

Since I am the original owner of an 83 Maxim, I normally don't care for many modded bikes/bobber/cafe conversions. However, I kind of like the overall retro look of yours. The white walls with the red paint on the inside of the rim looks very retro.

 

Thanks for the kind words.

I pulled the carbs off. There is some cleaning that needs done. The bowls had some crap in them. Heading to get a case of carb cleaner.

Looks like there has been people in these carbs before. Screw heads are rounded some and the jets don't have crisp edge's .

I'm going to clean these up some and put everything back together. Need to make a list of all the gaskets and what not that I'm going to need.

 

P.O. syndrome ....never know what has been done....If you continue running pods unless you have a bracket there, support the carbs relying on the boots can cause them to crack.

 

I was looking at that. What is the best way to support them? Should be pretty simple. The list is growing.

The air jets. Would I order them from the same place I get the fuel jets?

 

Chacal(xj4ever) or jets r us .com would be 2 sources . As to fabing a bracket that is up to you, I personally do not care for pods , all the bikes I've owned have retained stock airbox and ran great . You will find , you will have a flat spot, or hard to start, rich running etc . I had a friend was running pods on an 82 GS750 ( he bought it that way) he thought it ran great until he rode my 81 CB750 Custom with stock airbox ...he could not get over how it responded to throttle, idle ...he put airbox back on Suzuki and did not have to mess with carbs after that !!!.

 

I just picked up the parts bike it might have the air box in it. When I get it unloaded I'll take picture of what all I have.

 

Pic of the parts bike

 

Pile of parts I got with the bike

 

Been working on cleaning the enrichment wells in the bowl. Talk about a pain in a butt. 3 out of 4 opened up. Need to get some fresh air. Lol

 

There are some internal differences between the '80 and '82 carbs.

Also, between the engines---
'80 is non-YICS, '82 is YICS

There are some transmission differences, too, and some of those parts are not interchangeable

 

Last night I had time to work on the bike some. Finished getting the bowls cleaned and the jet opened.

Got the bike put together and bam the thing fired up. Went out this morning and fired up again. Thanks for all the help getting me this far. If I have time this week I'll get the valve tool ordered along with some jets and parts to rebuild the carbs.


Happy Independence Day everyone.

 

Here's the best valve tool money can buy.

 

I thought that would damage the valve guide?

 

It won't damage the GUIDE, but, in some cases could damage the valve stem guide OIL SEAL (if the valve gets a bit cocked, and hard, brittle valve seal could rupture).

 

Im working on ordering some parts. question I have now is for the jets.

Has 4 pods and straight pipes. per the information overload I have 8 sizes-2sizes. So up 6 jet sizes. Would that be Main jet #122?

Pilot is 1 per every 3 main jets increase. Going up 6 on the main would be 2 on the pilot jets. That would be #42.

 

And if the oil seal goes because of using the wire, it was going to fail soon anyway.

 

That's an excellent point. This week I'll try the wire method.

 

I did the fuse block upgrade. Worked great.

Turn signals and front brake light not working.

Tore the turn signal switch apart and found 2 wires off. Soldered them back on. Easy fix. Lights now work.

Front brake light. Ohmed out the switch and it works. I just need to look at the wiring diagram to verify the correct connect.

Thanks for all the great advice. I'm sure I'll be asking more after my parts arrive.