1978 R80/7 sputters

georgej

Member

• Jul 21, 2020

• #1

So my R80/7 sputters when I first open the throttle after she's warmed up. The bike idles fine, runs fine when I open the throttle. This only happens with the throttle maybe open a quarter of the way when starting from a dead stop. I took the bowls off no dirt or debris in them. Where else should I look. she's been running fine. No points on this one,Dyna electronic ignition already installed when I got the bike.

 

pglaves

#13338

• Jul 21, 2020

• #2

It sounds like something amiss with the needle jet as you are transitioning off the idle jet. It might be dirty causing a lean condition or it might be worn causing a rich condition. Remove it, clean it, and see what changes.

 

ebeeby

Member

• Jul 22, 2020

• #3

PGlaves said:

It sounds like something amiss with the needle jet as you are transitioning off the idle jet. It might be dirty causing a lean condition or it might be worn causing a rich condition. Remove it, clean it, and see what changes.

Click to expand...

+1 - sounds like carb transition.

 

roninbuffalo

Member

• Jul 22, 2020

• #4

Don’t know how many miles on Blake. But “top hats” “needle thrusters” are made of brass any they ware out which describes the symptoms you have questions about.

 

7

72r60/7

13278

• Jul 23, 2020

• #5

Check plug wires also.

Charlie

 

guenner

Member

• Jul 23, 2020

• #6

Enricher not closing/closed?

/Guenther

 

georgej

Member

• Aug 11, 2020

• #7

Thanks for all the replies and suggestions.I cleaned the pilot,main and needle jets. The problem persisted. I checked the plugs and they were good. I took the tank off to have a look and one of the plug wires was off the coil.Put it back on,she runs as smooth as she ever did.

 

20774

Liaison

Staff member

• Aug 11, 2020

• #8

Thanks for the update!

 

N

nickrides

Nick Kennedy

• Aug 11, 2020

• #9

Well that update kinda shoots a hole in the theory that not having the plugs grounded when cranking the starter will destroy the ignition system.
Nick
1978 R 80

 

stevenrankin

Active member

• Aug 11, 2020

• #10

Destroying the ignition system

For a 78 R80/7, unless the points have been replaced with an after market system, you can pull a plug and do all sorts of things with no problem.

DO NOT crank a 1981 BMW without having the plugs connected and grounded! You may get lucky one or two times but for sure, you run the risk of popping the ignition module under the gas tank.

This is not a theory but fact. St.

 

georgej

Member

• Aug 11, 2020

• #11

This one has electronic ignition. It was like that when I bought it 10 or so years ago.

 

20774

Liaison

Staff member

• Aug 11, 2020

• #12

Well, it was sputtering so it wasn't like it was fully open all the time. Maybe that's the saving grace.

 

stevenrankin

Active member

• Aug 11, 2020

• #13

So what ignition?

OkAY, I see the bike is a 78 R080/7. Does it have a stock electronic ignition or an after market system?

1981 was the year I believe the electronic factory system was introduced. At least as far as I can tell by a quick scan of Snowbum's information.

I am only warning about the stock system, but I would bet the aftermarket systems don't like to fire a ungrounded spark or what ever.

I don't know the number of times an electronic system can be abused before it goes kaput. Once, twice, thrice? St.