Wilsons Sandbox

On Thu, 1 Jul 2004, Don Bittle wrote:

> My A17 (4900 mi.) has a slight surge/miss in top gear when I'm highway > cruising. This is the only time it happens. I can get on it in any gear > and there is no miss right up to redline. Any ideas?

Fuel supply. Either your fuel filter is clogged, fuel screen is clogged, vacuum doohickey is failing for your fuel petcock (which will make it shut down fuel supply as vacuum falls -- such as when you have the throttle all the way open), or your float valve is getting constricted by gunk/deposits. Or your float bowl level is set too low (float too high) and you get intermittent fuel starvation because the float valve isn't opening all the way. There's other places to look, but fuel supply is the classic one here. -- Eric Green http://badtux.net/ mailto:eric@... June 15, 2003: the 100th birthday of George Orwell. War is Peace. Ignorance is Strength. Freedom is Tyranny. Welcome to 1984+20

Lots of KLR burnt piston stories have the common thread of running lean at speed for whatever reason. Often a fuel filter is involved. I would treat this as serious to the long term health of your motor and avoid situations that cause the symptoms until you can locate and repair it. Lee

----- Original Message ----- From: "Eric L. Green" To: "Don Bittle" Cc: dsn_klr650@yahoogroups.com> Sent: Friday, July 02, 2004 2:54 AM Subject: Re: [DSN_klr650] missing in 5th gear > On Thu, 1 Jul 2004, Don Bittle wrote: > > My A17 (4900 mi.) has a slight surge/miss in top gear when I'm highway > > cruising. This is the only time it happens. I can get on it in any gear > > and there is no miss right up to redline. Any ideas? > > Fuel supply. Either your fuel filter is clogged, fuel screen is clogged, > vacuum doohickey is failing for your fuel petcock (which will make it shut > down fuel supply as vacuum falls -- such as when you have the throttle all > the way open), or your float valve is getting constricted by > gunk/deposits. Or your float bowl level is set too low (float too high) > and you get intermittent fuel starvation because the float valve isn't > opening all the way. > > There's other places to look, but fuel supply is the classic one here. > > -- > Eric Green http://badtux.net/ mailto:eric@... > June 15, 2003: the 100th birthday of George Orwell. War is Peace. Ignorance is > Strength. Freedom is Tyranny. Welcome to 1984+20 > > > > List sponsored by Dual Sport News at www.dualsportnews.com. List FAQ courtesy of Chris Krok at: www.bigcee.com/klr650faq.html > Unsubscribe by sending a blank message to: > DSN_klr650-unsubscribe@yahoogroups.com . > > > Yahoo! Groups Links > > > > >

dbittle@... wrote:

>My A17 (4900 mi.) has a slight surge/miss in top gear when I'm highway cruising. This is the only time it happens. I can get on it in any gear and there is no miss right up to redline. Any ideas? > >

If it's slight then it won't cause any real damage. I struggled with this for weeks, but I didn't have a "slight" surge, I would have the motor fade and then enough heat would pour off that my right leg would get uncomfortably hot. I'm guessing as well that it's fuel starvation. If you have time, do these things one-by-one so you know what the problem is. If you don't then do them all at once- it solved the problem for me. 1- fuel tank venting, if the flapper valve in the fuel tank cap is sticking, or the fuel tank vent is blocked, this will generate a vicaaum and prevent fuel from flowing. A partial restriction will only be felt at prolonged highway speeds. Blow out the tube, gently blow out the cap. As a last resort, disassemble the cap and rip the guts out of the flapper valve with pliers. Now you have a dirtbike-style vent with no check valve. 2- an inline fuel filter. These have never worked well for me, they always intermittently restricted flow after working OK for a month or two. Make sure the screens are in place on the fuel tap, then install a fresh piece of fuel line with no filter. Or, install a brand new filter and then see if you get the surging. 3- Check the vacuum hose to the fuel tap. Sometimes they are a little too long, when the hose gets hot and soft it can kink. I converted my fuel tap to manual operation because I was having problems with this. I measured a different (intermittent) fuel bowl level with the vacuum tap, and a consistent level with the manual tap. 4- Have you modified the jetting at all? If the bike is bone stock, you might just be seeing normal lean-surging. Especially if you just cleaned the air filter. Devon

One thing to try, is to drain all but 2 gallons of gas, then mix in Techron or Seafoam at double the strenght on the label. Ride the bike for 1/2 hour, then let it sit overnight. Fill the tank the next morning and ride. This sometimes dissolves a bit of goo in the pilot jet. Next thing is the remove the pilot screw, and blast carb cleaner into the open hole. Wait 5 minutes, give it another shot, then reinstall the screw and ride it. If the half-ass shortcuts don't work, you have to pull the carb and clean it. But it might go away if you use fuel additives for the next few tankfuls. Devon dbittle@... wrote:

>No. I've not modified the carb. Another clue is that it didn't start until >the bike was "in storage" for 2 months. I've since ran 3 tanks of gas thru >it. >Thanks for all the help. You ladies are my best resource for help. >don > >. > 4- Have you modified the jetting at all? If the bike is bone stock, you > > >>might just be seeing normal lean-surging. Especially if you just cleaned >>the air filter. >> >>Devon >> >> >> >> >> > > >

I just thought of another clue. The bike has recently started pinging under certain conditions. I figured I'd try premium gas next time. I'll be taking contributions. don

> Lots of KLR burnt piston stories have the common thread of running lean at > speed for whatever reason. Often a fuel filter is involved. I would

treat

> this as serious to the long term health of your motor and avoid situations > that cause the symptoms until you can locate and repair it. > > ://groups.yahoo.com/group/DSN_klr650/ > > > >

No. I've not modified the carb. Another clue is that it didn't start until the bike was "in storage" for 2 months. I've since ran 3 tanks of gas thru it. Thanks for all the help. You ladies are my best resource for help. don . > 4- Have you modified the jetting at all? If the bike is bone stock, you

> might just be seeing normal lean-surging. Especially if you just cleaned > the air filter. > > Devon > > >

dbittle@... wrote:

>I just thought of another clue. The bike has recently started pinging under >certain conditions. I figured I'd try premium gas next time. I'll be taking >contributions. >don > >

That's another symptom of excess heat. If it was running fine on regular before, fix the fuel delivery problem. Devon

--- In DSN_klr650@yahoogroups.com, "Don Bittle" wrote:

> No. I've not modified the carb. Another clue is that it didn't

start until

> the bike was "in storage" for 2 months. I've since ran 3 tanks of

gas thru

> it. > Thanks for all the help. You ladies are my best resource for help. > don > > . > 4- Have you modified the jetting at all? If the bike is bone

stock, you

> > might just be seeing normal lean-surging. Especially if you just

cleaned

> > the air filter. > > > > Devon > > > > > >

You probably have some crud in the carb from it sitting in storage, which is causing a fuel restriction, which can cause the symptoms you've described. I had a slight stumble on my 2004 KLR when cruising at about 50mph, which was fixed by installing a jet kit. I vote for cleaning your carb, and if you have the cash, install a jet kit at the same time. Keep us updated!

Called Avon today. Both Gripsters and Distanzias are still available. And they are still recommending mounting the front Distanzia on a KLR (and F650) backwards. Whoever told you they were no long available meant they (your supplier) did not have them in stock. Globerider Greg, on Gripsters by choice __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - 100MB free storage! http://promotions.yahoo.com/new_mail