backfire.......

[Tumu Rock]

My KLR backfires when shifting out of first. More of vroooompffft than a loud backfire. I can get rid of it by adjusting the idle mixture so it idles at about 15-1600rpm but I know it's supposed to idle between 11-1300. Is this a problem I should worry about or just set the mix and forget about it? It's completely stock carb, airbox, and exhaust (with a swiss cheese butt plate). Had the problem before drilling the holes though. dat brooklyn bum _______________________________________________________ Get 100% FREE Internet Access powered by Excite Visit http://freelane.excite.com/freeisp

[Jim Hyman]

Tumu Rock wrote:

> My KLR backfires when shifting out of first. More of vroooompffft

than a loud backfire. I can get rid of it by adjusting the idle mixture so it idles at about 15-1600rpm but I know it's supposed to idle between 11-1300. Is this a problem I should worry about or just set the mix and forget about it? It's completely stock carb, airbox, and exhaust (with a swiss cheese butt plate). Had the problem before drilling the holes though.

> dat brooklyn bum

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Bum, Remove your carb, rotate 180 degrees (either way) ... just kidding! Rule out exhaust leaks first. Loosen all exhaust nuts, cylinder head, header junction, & muffler. Re-tighten everything starting at the cylinder head & working your way back to the muffler. Were you adjusting the idle-mixture or idle speed screws? The idle mixture screw is normally set at 1-1/2 to 3 turns out, according to the list. What me worry? Professor '95 KLR650 A9 Federal Way, Wa [USA]

[guymanbro@excite.com]

> Were you adjusting the idle-mixture or idle speed screws? The idle > mixture screw is normally set at 1-1/2 to 3 turns out, according > to the list. >

Oops, I guess I meant the idle speed screw...the backfire is getting worse by the day. Is the mixture screw inside the carb or somewhere else? I'm gonna break open the manual when I get home this morning. Been having some kind of server problem..got no messages Thursday blah blah blah.

[Jim Hyman]

> > > Were you adjusting the idle-mixture or idle speed screws? The

idle mixture screw is normally set at 1-1/2 to 3 turns out, according to the list.

> >

--- guymanbro@e... wrote:

> Oops, I guess I meant the idle speed screw...the backfire is

getting worse by the day. Is the mixture screw inside the carb or somewhere else? I'm gonna break open the manual when I get home this morning. [snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Guy, Don't rush in & start fiddling with the carb just yet. Get some feedback from the list first. I can't tell you how many (unnecessary) customer repairs I've had to 'undo' over the years. One of the most common ones is attempted carb adjusting,repairing or tweaking. You said that your airbox, engine & exhaust are stock, and that the 'backfire' existed before you swiss-cheezed the muffler. Several questions: Is your bike running well. except for the backfire? How's the power? Gas mileage? Does it pull strongly & smoothly? Does it stumble or hesitate at low, mid, or high-speed? Any black, white or bluish smoke coming out of the exhaust? Most important: When did this problem start and were there any changes to your bike just before the problem started? Over the years, I've fixed many bikes where the problem was poor running & the culprit turned out to be something like "yeah, I blasted the engine clean with my 25,000 psi industrial washer!" Many (or most) problems are the result of something done to a vehicle prior the the onset of the problem. Right now it's kinda like "hey doc, I don't feel good - what's wrong?" Professor '95KLR650 A9 Federal Way, Wa. [USA]

[Jim Hyman]

Bum, Follow Tobin's suggestions about an exhaust leak at the juncition of the exhaust pipe & the cylinder head. This is probably the source of your problem. Ignore the puff of white smoke at startup. The noise your hearing may be occurring every time you shift, but is masked by wind noise. It sounds like you have a minor "lean" condition with the fuel mixture. I don't think that it's a fuel level problem in the carb's float bowl. It's possible that a minor air leak around the "choke" enricher (enrichener?) could cause this problem. Be sure to loosen all exhaust system mounting bolts before tightening the exhaust pipe in front. Professor '95 KLR650 A9 Federal Way, Wa. [USA] ps: good gas mileage, do you ride in wimp/wuss mode? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> > On Fri, 05 May 2000 10:11:02 -0000, Jim Hyman wrote: > > > > You said that your airbox, engine & exhaust are stock, and that > > the 'backfire' existed before you swiss-cheezed the muffler. > > Several questions: > > Is your bike running well. except for the backfire? > > How's the power? Gas mileage? > > Does it pull strongly & smoothly? > > Does it stumble or hesitate at low, mid, or high-speed? > > Any black, white or bluish smoke coming out of the exhaust? > > > > Most important: When did this problem start and were there any > > changes to your bike just before the problem started? Over the > > years, I've fixed many bikes where the problem was poor running > > & the culprit turned out to be something like "yeah, I blasted > > the engine clean with my 25,000 psi industrial washer!" > > > > Many (or most) problems are the result of something done to a > > vehicle prior the the onset of the problem. Right now it's > > kinda like "hey doc, I don't feel good - what's wrong?" > > > > Professor '95KLR650 A9 Federal Way, Wa. [USA] > > >

--- Tumu Rock wrote:

> I just bought the bike used in January and noticed the backfire

about three

> weeks ago (could have been there all along but as I get to know the

bike I

> notice more and more). Haven't changed anything on the bike with the > exception of replacing missing bolts and fiddling with the idle

speed screw.

> No power shortage, mileage per tank is right around 300, sometimes

a tiny

> bit of really faint white smoke during warm up. Could it be

something as

> simple as a bad spark plug? > > It's a '96 and I doubt if anything has been changed since new

(looked like

> it had been garaged for a while when I bought it). > > dat brooklyn bum > > > > > > _______________________________________________________ > Get 100% FREE Internet Access powered by Excite > Visit http://freelane.excite.com/freeisp

[guymanbro@excite.com]

--- In DSN_klr650@egroups.com, "Jim Hyman" wrote:

> > Bum, > > Follow Tobin's suggestions about an exhaust leak at the juncition > of the exhaust pipe & the cylinder head. This is probably the > source of your problem. Ignore the puff of white smoke at

startup.

> The noise your hearing may be occurring every time you shift, but > is masked by wind noise. > It sounds like you have a minor "lean" condition with the fuel > mixture. I don't think that it's a fuel level problem in the > carb's float bowl. It's possible that a minor air leak around > the "choke" enricher (enrichener?) could cause this problem. > Be sure to loosen all exhaust system mounting bolts before > tightening the exhaust pipe in front. > > Professor '95 KLR650 A9 Federal Way, Wa. [USA] > > ps: good gas mileage, do you ride in wimp/wuss mode? >

I'll take a look at the junction on Sunday (Saturday is a hell day at work for me...get out at 7am be back at 3pm). And no I don't ride in wimp/wuss mode but I rarely get out of 2nd gear in city traffic and until yesterday hadn't ridden for the sake of the ride (I just got legal on Wednesday!) It was a blast. Next weekend I'm heading to Massachusetts to see the in-laws...that should be a better test of my riding mode than anything I've done so far (although I actually probably will ride in wuss mode for most of that trip cuz the wife will be on the back and she prefers the wuss mode). In my defense, on my 50 mile lap around the belt parkway with my friend who has "ridden all his life" I could barely keep him in rear-views even while splitting lanes. dat brooklyn bum

[Jim Hyman]

Bum, If you're going to be in the Boston area, WARNING: The golden rule there is: Do unto others BEFORE they do unto you. I know, I grew up there. RIDE SCARED and expect the unexpected from other drivers. Have a safe trip. Professor ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

--- In DSN_klr650@egroups.com, guymanbro@e... wrote: > Next weekend I'm heading to Massachusetts to see the in-laws... > dat brooklyn bum

[Dan Mullins]

Anyone know what I can do to get my KLR to quit backfiring? After I replaced the choke cable (the bike was on choke all the time), it started backfiring slightly during decceleration (engine braking). It seems to me that the choke is working properly but it has caused the bike to backfire while riding the bike on the normal "run" position. Thanks, Dan A8 Detroit Dan A8 Detroit --------------------------------- Do you Yahoo!? vote.yahoo.com - Register online to vote today! [Non-text portions of this message have been removed]

[dooden]

Check the exhaust clamp behind the rear brake cylinder above/behind the right foot peg. Ensure this clamp it tight, also check the nuts at the front of the pipe where it bolts to the motor. Have you drilled/set your pilot circuit to about 2 full turns ? Check the FAQ: http://www.bigcee.com/klr650faq.html Fuel / Intake (from FAQ) Why does the bike pop on deceleration? The bike is jetted very lean from the factory. You can enrich the idle mixture by removing the pilot screw cap and backing the screw out 1/2 to 3/4 turn from its factory setting. (The pilot screw is located on the engine side of the carb, in front of the bowl, on the bottom. It is underneath a plug, which must be drilled through to remove.) Note that it may be illegal to tamper with carb settings in your state. Note that this symptom can also indicate an exhaust leak, so check all of the exhaust connections first. http://members.aol.com/roundr1/CVK40.html Shows the carb in detail. Dooden (Yooper) A15 Green Ape Please do not feed the trolls.....

--- In DSN_klr650@yahoogroups.com, Dan Mullins wrote: > Anyone know what I can do to get my KLR to quit backfiring? After I replaced the choke cable (the bike was on choke all the time), it started backfiring slightly during decceleration (engine braking). It seems to me that the choke is working properly but it has caused the bike to backfire while riding the bike on the normal "run" position. > Thanks, > Dan > A8 > Detroit > > > Dan > A8 > Detroit > > --------------------------------- > Do you Yahoo!? > vote.yahoo.com - Register online to vote today! > > [Non-text portions of this message have been removed]

[Bill Whalen]

My KLR has a Supertrapp Exhaust, K&N Air Filter, and Dynojet Kit. My bike was running fine uder 5000 rpm's, but over that it would miss badly and could not go over 70-75. I removed the carb, took it apart carefully (have done this about 4 other times with problem), cleaned it with carb cleanier, and reassembled. The bike starts immediately, and pulls strong throughout all the gears to redline without a hint of a miss. The two problems I have is that on decelleration it backfires terrrible and it seems to be running slightly hot. I have the thumb adjuster screw and it I put it at 2, 2 1/2, 3, 3 1/2, and 4 turns and the bike seems to run the same and the backfire is the same. I also went from 6 disc's to 9 in the SuperTrapp if that makes a difference. Also, when the thumb screw is all the way in is it richer or leaner, I thought that I red somewhere that it is the opposite of most carbs. Any help with be greatly appreciated. Bill "SandShark" 92 KLR-650 03 V-Strom