• Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

Theory On Our "Stalling/Stumbling" Issue

It's on the right side just behind the frame rail above the valve cover. It's only on those bikes with a fuel vapor emissions canister.

So it's just emissions crap? If so, can it be cut out of the loop without any effect on performance later? Will it alter the way the ECU learns?

This begs another question: Do bikes from countries that don't require the canister experience these problems? If so then could we be looking at multiple potential problems, which is making a solution harder to find.

If all the fuel wasted from poorly running vehicles as a result of pollution control equipment since 1970 were added up it would probably amount to 20% of all the fuel burned in that time.
 
The tank vent valve is only on the US models and it is included in both the fault monitoring and diagnostics tests for engine ECU's. Same deal with the BMW Rotax models. If you check the testing results from DRZCharlie they show it pulsing and also the injector timing being reduced when it is open to the inlet. When removing it it would seem you would need to also reprogram the BMS-E to ECE firmware to stop the reduction in injector timing when the BMS-C believes it is active
 
Yes, it can be removed with no ill effects. Many, many people have. I have left my emissions systems in place, with no ill effects. It has been shown to be a potential problem in the past. As with most of this TR, YMMV.
 
My guess is something else is causing a rich condition and plugging the purge hose is effectively leaning the mixture.The purge valve is quite active on this bike.Here are a couple screen shots from my o-scope of the purge valve in operation.

(of course there is always the possibility the purge valve was stuck open on the bike in question)

This is at idle,green trace is injector and yellow is purge valve,sorry about the line hash and the cutoff tops ,I was only interested in the "on" time

cannister%20operation%20at%20idle-L.jpg


and at 3k RPM

cannister%20open%20time%20at%20rpn-L.jpg

Thank you for the info and scope shots, very interesting.
The Purge Valve on the bike in the video was faulty and leaking air in creating a 'lean condition' not a rich one.
Plugging the hose between throttle body and valve completely cured the crappy running and 'random' stalling issues.

My theory is that this is occurring on more than one bike and could be the cause of the stumbles, but I need to test it a little more.
On my bike there is no cannister but I still have the valve so I will use it to test the theory that the bike stumbles when the valve is in operation.
 
The Purge Valve on the bike in the video was faulty and leaking air in creating a 'lean condition' not a rich one.
Plugging the hose between throttle body and valve completely cured the crappy running and 'random' stalling issues.

My theory is that this is occurring on more than one bike and could be the cause of the stumbles, but I need to test it a little more.

You could be on to something here,but without a poor running bike and some test equipment its hard to verify.

Actually,I think since there is no Mass airflow on this bike to meter the airflow entering the engine the actual lean condition comes from the fact that all available fumes have been sucked from the cannister and the leaking purge valve is allowing pure air to be pulled thru the cannister and into the engine,which the o2 immediately reports to the ecm and it responds by going full rich to compensate for high o2 and causing crappy running.All theory of course...:)

I Here is a graph from my LM2 while I was pinching and releasing the purge hose.You can see how much effect it has on the fueling

cannister%20operation-L.jpg
 
Hi big-t, Good chart. It looks like the rpm dips when you pinch the hose. The AFR on the Terra is not that well controlled by the ECU but I don't see any signs that it goes full rich.
 
  1. The AFR on the Terra is not that well controlled by the ECU but I don't see any signs that it goes full rich.



Roger that was just some speculation on the leaking purge valve issue posted by Mark_h
 
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