would these work?

Hello all! I bought my bike a 81 xj650 and am having the backfire through the carbs, from what i've researched on the problem is the Intake to Carb boots. When i looked at mine they are very dry rotted and cracked.

I found a set on ebay for sale for a 82 xj650 seca. would there be any problems fitting them onto my carbs/intake? My carbs are recently cleaned and have determined the problem to be the boots. any info at all would help! thanks!

 

Let's be sure we aren't chasing our tails!

Run the Bike.
Spray Carb Cleaner on the MANIFOLDS.
IF, ... the rpm's rise -- Buy the used Manifolds.

The BIGGER Problem is what's going to happen when you need to take the OLD Manifolds OFF.

Those Manifold Bolts are SOFT Steel.
They might be SEIZED in the Head.
Braking them off is Bad News because to fix the Problem you might need to take the Head off and send it out for Machine work.

Who knows?
It's a Crap Shoot.
The Odds are 8-to-1 against you.

 

just a side note- if it ends up being the boots, and you want to risktaking the bolts off, but some KROIL -off the internet... and let the bolts soak for a day... a member on here reported success doing that...

 

If the manifolds are leaking don't take them off if it looks like you are going to shear off the mounting bolts.

Repair the manifolds in situ using hoops of cycle innertube rubber secured by high temp RTV sealant. It will look a neat job! Not to mention less than a few $$ to do it.

 

The TERRIBLE thing about the Manifold Bolts ...
You THINK the Bolt is coming-out.
But, ... it's actually -- Twisting; until it breaks.

 

FML! haha well there is another set on ebay also with the manifold attached to the boots...not sure i believe it came off an 82 650 but i can't remember. I guess im probably better off just fixing the old ones with the RTV and stuff? hmmm

 

The pedal bike tube thing worked really nice for me. It looks a lot better than smearing rtv all over the boots too.

On a different note have you check your valve clearances lately(past 5k miles)? You may have some tight intake valves.

Good Luck,
James

 

no i havent checked them at all...i just picked up the bike from my buddy, not too shabby for $400. it has about 40k on it but I had him take it to his dads auto shop and he cleaned the carbs...thats about as far as i know that has been done recently.

Its definatly a budget bike to get me from home to work/school. So Im trying to keep the spending down on it. what size inner tube is it? and are they all the same size? i have no idea when it comes to that. Or is their a how-to?

 

03saab93t:

Lets get you on the road.
Go to:
Your Account ...
Fill in:
LOCATION.
Open Signature:
Enter THUMBS about your Bike.

Year Model Mileage Stock or Mods.
---------------------------------------------

You STILL might need to have your Carbs Cleaned.
An Automobile Service Technician isn't inclined to spend a good deal of time on a Non Work-ordered job.

You might have had the Carbs looked at.
But, we NEED to know if they got "The Full Monte"
Unless all four got disassembled and cleaned, ... that leaves you NEEDING a Carb Cleaning.

Get your Location & Thumbs displayed.

 

The way I took manifold bolts off...soak in PB Blaster (or your favorite lubricant for stuck fasteners). Spray all around the screw and manifold bolt an HOPE some gets in the threads. After doing that a couple of times (and waiting hours for it to soak in between applications), get your allen key out. Place the allen key in at an angle such that you can strike into it gently, hitting it both toward the engine and counter-clockwise (remember righty-tighty...lefty-loosy).

It worked for me but I might have been LUCKY. The theory is...if the screw is soft, it will deform under a constant torque (turning with a wrench)...but may just absorb a larger shock load (or impact) without actually causing deformation. The corrosion is brittle, and doesn't do well with a shock load (failing catastrophically) compared to a constant torque.

 

Depending how long the bike sat or mileage. Your problem could be throttle shaft seals. They get hard and sloppy. When you check the manifolds with carb cleaner or other. Spray the ends of the throttle shafts and see if you get the same result. Higher rpm, or bog down,is a sign of worn seals. The manifolds are double walled. Just because they are cracked on the outside doesn't mean they are cracked on the inside. They also have a spray rubber insulator. If they are cracked, you could put a few good coats on and it should seal them. The valve adjustment is very important too so check them.

 

I want to dip my hand in that stuff.

 

+1 on the PB Blaster. I just did this to my XJ 550 this weekend. Sprayed the PB blaster all around the boots, for a day (about once an hour). Then used a flat head scew driver to tap out around the head of the bolt. Then just put the hex head in, gave a few good tapperooos and boom all 8 came out without a hitch.

I am sure that karma was on my side for this, but i do think that the PB Blaster helped ALOT! And on a side note, between a quick carb clean, fresh bench sync, and the new boots, my bike is running awesome. Starts better and runs like a champ. Good luck.