Question about 1987 Honda XR 250 R

1 Answer

Hi, I have a 1980 Honda XR250. The compression is around 120 (with decompression disconnected). It blows smoke and will not rev high - I assumed carb dirty, cleaned it but still reluctant to go to high revs. Any advise welcome !

Posted by on


1 Answer

  • Level 1:

    An expert who has achieved level 1.

    New Friend:

    An expert that has 1 follower.


    An expert that has over 10 points.

    Welcome Back:

    Visited the website for 2 consecutive days.

  • Contributor
  • 5 Answers

Might be a good idea to check your timing first and then if the timing is ok try removing your exaust pipe and running it for a few minutes without the exaust system installed. I have encountered a couple of bikes where the exaust system has carboned up and will not allow the engine to breathe especially at hiogher rpms. A day in the gunk tank for the exaust pipe did the trick and the bike ran like new. (Gunk will remove all the paint too)

Posted on Jan 22, 2013

Testimonial: "timing checked, one inlet and exhaust valve tight, and one blocked exhaust pipe - challenge is fining a pipe now"

  • Andrew Foster Apr 07, 2013

    yep the pipes were blocked (collapsing baffles etc) - these were repaired and runs a damned sight better now, but one header pipe heats faster that the other. I painted the headers with hi temp paint one pipe burnt the paint off, the other is still good. would that be a beurnt out exhaust valve causing this ???



6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017

  • 3567 Answers

SOURCE: 1980 honda cx500 will sart with the chok pulled

This sounds like the main jets are varnished up and possibly the float(s) are sticking. Pull the carbs off the bike and clean them with carb cleaner. Remount the carbs then balance and sync them. On a bike that old I would spring for carb rebuild kits. The kits MAY have additional parts for other carbs along with yours. Just use the parts that match the ones from your carbs.

Posted on Mar 17, 2009

  • 2 Answers

SOURCE: i have a honda magna vf750 the no1 carb keeps

there is a liquid you can buy it is called seafoam, I had the same problem I put it in my gas, ran the bike for 5 minutes , everything worked fine

Posted on Apr 16, 2009

  • 3567 Answers

SOURCE: i have a honda magna vf750 the no1 carb keeps

Drain the carburetor. There should be a screw on the lower side of the carb float bowl. Remove the screw then replace it after the fuel drains. Turn the gas back on and wait a minute for the carb to fill with gas. Start the engine. If the bike doesn't start and run properly then shut off the gas and remove the carburetor from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb.
clean the air filter and install the carb. Let the float bowl fill then start the engine.

Please rate this solution. Thanks!

Posted on Apr 16, 2009

  • 248 Answers

SOURCE: i have a honda CB400 super four and have been having a slight pro

Your carb may be adjusted a little lean. Try adjusting the needle, keeping track of the changes you make, and blipping the throttle full to check the result.

Posted on Jul 28, 2009

  • 496 Answers

SOURCE: 2001 Honda Shadow ACE 750 idles, but won't rev up

vac leak craked boots

Posted on Jan 05, 2010

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

1995 Honda XR 250 R reinstall carburetor

Hi, Miguel for this scenario you will need your service manual, parts fiche, and owners manual if you can't find the best tool you ever bought for your Honda, despair not, for a mere zero $0 you can download another one.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day.
1984 Honda XR 250 Carburetor Removal
xr250 carb part 1
Honda XR250R Service Manual
Honda XR250R Owner Manual

Dec 29, 2017 | 1995 Honda XR 250 R

1 Answer

Is there a low speed jet adjustment on a honda ex1000 generator(ea4-1212412

You have dirt in the carb, remove it and rebuild it and blow out all the passages with compressed air.

Mar 15, 2017 | Honda Portable Generator Model Ex1000

1 Answer

1985 honda xr250 blowing air out the carbs

Air blowing back from the carbs is a sign your intake valves are leaking. They do this when there is not enough gap between the valves and the rocker that opens the valves. They need to be set to 0.003 inches when cold and with the piston at top dead center of the compression/power stroke

Feb 28, 2014 | 1985 Honda XR 250 R

1 Answer

Honda xr250 headlight goes dim when reving, it

Stator/magneto failing. takes more juice to rev the bike, so it takes from the lighting.

Sep 25, 2013 | Factory Effex F Effex Shroud Decal Xr250...

1 Answer

Has hesitation at acceleration. rebuilt both carbs, adjusted acc. pump. when i synced the carbs, the gauges were jumpy, could not get them to steady. one exhaust pipe stays cool much longer than the other...

hi,although you have done all that it still sounds to me like you have a carb problem,one cylinder is obviously not getting enough fuel,the difference between right and wrong when you are balancing carbs is less than 1/100th of a turn on the adjusters,you have to be very precise,also did you check that the mixtures were set corectly before you tried to balance the carbs,hope this helps...cheers

Apr 29, 2010 | 1980 Honda GL 400

1 Answer

Can't find compression specs for 1980 Yamaha 650G

The compression should be around 150psi, but at 120psi it should pop, try to readjust the valve clearance.
Hope this helps!

Jun 21, 2009 | 1980 Yamaha XS 650 G

1 Answer

Y wont my brand new xr250 2005 model go faster than 90kms

It is possible that your bike has been governed from the factory to only reach a certain maximum RPM, they do this so you don't inadvertently over rev the engine and blow it up.

If the bike is not governed you might have to re jet the carb, altitude and other factors can change your fuel/air requirements and cause improper operation of your fuel system therefore the maximum RPM.

Jun 07, 2009 | 2005 Honda Xr 250

1 Answer

Bike smokes when

Hey Alan, you did'nt say what mileage but i suspect high mileage on a 1980 bike. A compression test is easy on a 2 cylinder and will probably result in a low reading on the side that smokes. Also the chke could be closing tighter on the carb on the smokey side causing too much fuel to enter and also cause smoking....The short time you need to choke a bike in summer is a small price to pay on a bike that ride and enjoy, you're not damaging anything by riding it that the way, i love those old Yammer 650s...Good Luck to you friend.....Tim

May 09, 2009 | 1980 Yamaha XS 650 G

2 Answers

White smoke coming from exhaust

White smoke could indicate coolant in the combustion chamber. Not likely if you have an air-cooled bike. It could also mean that you are running in a cold climate, if the temp is around 20 or less I would call this normal.

If your bike is water cooled I would keep a close eye on your coolant level and oil level. A blown head gasket could allow water to get into the combustion chamber (causing the smoke) or mix with the oil (even worse). If you notice it using coolant I would have it checked out by a mechanic. If you want to check it yourself, do a compression check on both cylinders. If one is rather low, there is your problem.

Jan 12, 2009 | Harley Davidson FLSTS Heritage Springer...

Not finding what you are looking for?
1987 Honda XR 250 R Logo

181 people viewed this question

Ask a Question

Usually answered in minutes!

Top Honda Experts

Arnie Burke
Arnie Burke

Level 3 Expert

4825 Answers


Level 3 Expert

79186 Answers


Level 2 Expert

342 Answers

Are you a Honda Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides