Misfire- The lady that interrupts... ????

[Ross]

Cheers again guys.

Its not like I do the speeds I did to show this up all the time. Country road no other traffic.

[Jean]

So, tell us what you eventually find. I'll vote for restricted fuel supply at this time, too.
How long did you say since you went this fast, 2-up?Tell more about the R80/R100 designation, too. Do you mean you have an R80 bottom and R100 top end? or just what.?
If what I suggested is really the case, I'd install 140 main jets, needle in 3rd position.

[Ross]

So, tell us what you eventually find. I'll vote for restricted fuel supply at this time, too.
How long did you say since you went this fast, 2-up?Tell more about the R80/R100 designation, too. Do you mean you have an R80 bottom and R100 top end? or just what.?
If what I suggested is really the case, I'd install 140 main jets, needle in 3rd position.

I wont get to have a look at the carbs till next week.

Been some time since I have had a chance to wind the bike out 2 up. Thinking about this maybe doing this 2 up is reaching the limits of its top speed 2 up???

R80 short motor. 1983. My 1994 R100 barrels and heads. Why? Because I pulled a cylinder stud that had already been helicoiled and could not take a case saver. See http://rossmz.blogspot.com/search/label ... der%20stud for the horrid story.

Have found with the 140 main jets that the bike eats fuel quicker than the 135s. Staintune, who made my exhaust, told me that 135, as standard, are fine with this system. I may put the 140s back in and leave them. see what happens when I start to fiddle the floats.

I can't move the left hand needle as the nut that holds it wont come undone. I hope to get this fixed next month.

[hools100RS]

I had similar symptoms to those you describe and after fruitlessly stuffing around with coils, carb o-rings, etc, tracked it down to flogged out needle jets !!! An easy replacement and instant results. Good luck!!!! :

[Jean]

Right, hools... I have not ceased to be astonished at how much gum and gook can accumulate in the various ports when a bike is not used often. The main jet tube is composed of a lot of small assemblies and I got foxed by thinking they were clean once...didn't take it totally apart...and ended up redoing the job. THIS time completely undoing the main jet tube and finding "stuff" restricting the WOT fuel flow!!

How did the tank intakes look, tho? That is the first place to look if the carbs are in good shape (frequent use).
Which "number" carbs do you have, we know they are 64/32/?????

[Ken in Oklahoma]

It has a new coil.

That's good, but don't completely dismiss the coil from your thoughts. It is possible for a new coil to fail.




Ken

[Jean]

Oh yeah. The coil. Especially if it's one of those double-ended single coils that get too hot and split and short. I interpret "A" new coil to mean it's one of those.
M R100s broke-up bad at speed before I changed out the original coils, and they were in metal cans...Of coourse, they WERE nearly 20 years old...

[Ross]

This is the coil I put in about 6 months ago....

R2V MODELS 1985 >
DUAL OUTPUT 12V (BMW OEM)

Bought from Munich Motorcycles.

[Ross]

Today the floats heights were checked. They are good.
Fuel tank drained and lots of gunk found in one of the in tank filters.
Found this plastic bullet type thing with 4 weighs built into it in the tank. WTF?



Putting the bike back together and as I am putting the right hand throttle cable back on I stick my finger on some wire. Again WTF. I look down and the throttle cable is frayed not too far up from the nipple. I had suspected it was the right hand side that was playing up.



Looks like the frayed bits were catching and not allowing the right hand carb to open as far as the throttle grip was. This would explain the hesitation at the upper end of the bikes speed range.

I have had new throttle cables waiting to be fitted for about 12 months. They are now.

[Ross]

I found out what that thing was that came out of my fuel tank...

It's a Fitch Fuel Catalyst!

http://www.fitchcatalyst.com/recreational_vehicles.php