Intruder needs help or maybe just getting tired?

[mswyka]

Took our 79 Intruder for a ride yesterday - well actually I went out on the 78 but then switched for the ride home and brought back the 79.  It idled fine, and ran OK, so long as it was going slow, but really refused to do anything past half throttle.   

Pulled the plugs today.  Both plugs look good.  Compression test shows 135 on both cylinders. Swapped in a set of freshly rebuilt carbs and she ran the same way today.

Sled has 2,5XX miles and we added fresh pistons and seals in 2006.

Thoughts?

[Lloyd (ljm)]

Just wondering .. exhaust resticted?
                            sticky clutch?
                             bad bearing in the drive train somewhere?

[bryan_damone]

Does it rev up with track lifted? That may help determine if the problem is in the clutch(s), bearing, track etc.

[jimvw57]

try using the choke or primer and see if it is a fuel related problem.

[mswyka]

Thank you for the suggestions.  I didn't think about a clutch problem.  I will check that out. 

Jim, I did play around with the enrichener a bit and with the engine running adding fuel knocked down RPMs.

We also thought about an exhaust restriction.  we will have to swap in a nicely tuned exhaust  to see what happens.

Thanks.

[mswyka]

Over the weekend we were able to spend a little time with the sled.  Continues to start and run reliably up to 1/2 throttle.  Popped on a different primary clutch and at first I thought it ran a little better, but after a little riding I concluded that it had made no difference.  That was as far as we got.

The good news for the day was that we got our 80 Intruder running after swapping in a fuel pump that would actually pump fuel.

[kawhead]

i'd swap exaust pipes.....

[mswyka]

i'd swap exaust pipes.....

Tom, glad to have you back.  I will try that.  I also want to talk with you about our power trim ;-)

[mswyka]

Spent some more time with the sled today.  Our temps are warm and the snow is soft.  Pulled the exhaust with the intent of swapping in another.  The other one that we have with the same mounts was a little too short to fit onto the exhaust manifold.  But checking the exhaust with a fish wire and blowing it out did not reveal a restriction.  So it went back on and I took it for a ride.  Early part of the ride it seemed to run well and could go past half throttle easily - not as much pep as the 78, but not bad.  As the ride got longer it  fell back to the same behavior.  I am confident that it is not carbs since the carbs we took off went onto another sled and run just fine.  So at this point I am suspecting that the engine needs to be torn down.  Well, before I do that, the one last thing that I should probably check is whether or not the primer is leaking.

[Intruder alert]

I have '79 intruder that is behaving exactly as you have described the problems you are having with yours. I have swapped many parts with another intruder and nothing has really changed the performance. I have changed carbs, clutches, exhaust pipe, in addition to replacing the plugs and coil with new. I am suspecting air leaking in from somewhere, but carb gaskets and mounts look good. My next step was going to be to eliminate the primer lines, but now I am waiting for some snow.  I am wondering if I have an engine seal leaking since this motor has been sitting for ten years?

[mswyka]

If the sled has been sitting, and if it has not been torn down and inspected there is a very good possibility that the sled could have one or more issues.   I would encourage you to take it apart and check everything, and while it is apart to change the crank seals.

[mswyka]

So this evening I get a few free minutes and go out to check on whether the sled is sucking fuel through the primer.  I don't know what I was thinking or expecting since all our snow is gone and I can't ride it anywhere.  But I check none the less and nothing is obvious, no bubbles pulling through the system.  But I put a clamp on it anyway and no major change in operation.  But what I started to notice is that the engine has a distinctive "clack"  It is running well enough, but there is this clacking sound like something somewhere is vibrating.  Checking just about everything that I could everything points back to the engine - nothing that I check around the outside is vibrating or shaking.  We need more snow. 

[Interceptor398]

I have had loose bushings in a clutch make a clacking sound.

[mswyka]

I have had loose bushings in a clutch make a clacking sound.

I will change the clutch again and see what I get.

[Lloyd (ljm)]

 Mark

 Did it make the clacking sound at all rpms? or just low rpms?

 The clutch would likely quiet down at higher rpms.

 Lloyd