Bike almost dies after emergency stop.

Ive had to squash the breaks hard a couple of times.

Both times the bike almost dies in spite of having the clutch in and geared down. I then need to accelerate right after and the bike was sooo boggy for 3-6 seconds after the emergency stop.

 

Thats a doozy.

Float heights all in spec? Do you have an in-line fuel filter?

When you think about what's going on inside the carbs during an emergency stop, all I can think is the floats are out of spec, causing either a flooding or starvation issue.

Maybe the vacuum line to the petcock is old and collapses under the sudden increase(?) in vacuum...

I'd replace the vacuum line to the petcock, then give is a few tries to see what happens.

Ride safe...

 

Valves in spec? floats set properly? Pet in good working order? These are the first things I would check.

 

Float levels first.

 

Thanks I will see what I can do...

I'm still new, so a carb break down is kind of out of my league for now.
I can check the Fuel valve and vacuum line as suggested though

I was looking at getting one of those see-through filters (glass and chrome looked pretty cool) last time I was buying stuff for the bike. Is this something y'all recommend?

 

Yes, an in line filter is a good idea.

 

How do you fit it? I don't have enough room in the line.

Chris.

 

Yes you do.... You just have to get some rubber fuel line and then cut it in half and put the filter in the line.

 

It's a very tight fit. The smaller the better. I got a couple of the 90* filters from Len the last time I ordered.

 

Those filters at my local shop have a "for one or two cylinders." Mine is a 4 cylinder.
Also, I wanted to keep my fuel line in the tab where it's supposed to go.
Thanks for the picture.

 

@OP: You have a nice bike. At some point in the near future you should tackle those carbs. They will continue to have problems until you do. Plenty of help at this site.

@happydog: Once you install the filter you'll be glad you did.

Gary

 

I have two lines coming of the cock. Which one do I put the filter on?

 

The line going to the carbs. The other smaller line is not a fuel line; it's a vacuum line.

Gary

 

Both are the same size.

 

Then somebody replaced the vacuum line with fuel line and you should fix that.

Vacuum fuel valve tech: http://xjbikes.com/Forums/viewtopic/t=25058.html

There is a line that feeds gas to the carbs (that's the one you put the filter in) and another line that goes to a fitting on top of the #3 (650/750) or #2 (550) intake manifold. That line is the vacuum signal line and should be real vacuum line not just "hose."

 

Yup, fuel level changing too much during hard stopping. Been there.....

 

My question may be a bit off topic here but couldn't help but notice the vacuum line off #3 for 650/750 xj's. Is there really a performance difference. My 750 came from PO with it on #2 and I've left it that way. Will I notice a difference if I move it to #3?

Seems to me Vac is Vac.

 

In your case, vac is vac.

Some of the later 600s had jetting differences in #2 (where the vac line is supposed to be on the 550/600s.)

But not on the Hitachi equipped bikes. You're good putting it on any vac spigot you want.

 

Thx ..... as I'm still trying to get this beast to run properly. trying to eliminate any small variances.

 

Funny I call my The Beast as well....