Question about 1985 Suzuki XN 85 Turbo

2 Answers

Xn 85 fouling spark plugs

I have just managed to get my XN running after approx 10 yrs in bits ( stripped by many different owners ) and I have a continual problem of fouling number one spark plug. It runs for about 10kms ( 6miles) then drops one (number 1) cylinder. Any thoughts?

Posted by on

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 5 Answers

I have a xn 85 model 86 and it was in a garash for a many years so the rubber of the valve seal are wet and no stop the oil, in my case was the 3rd cilinder i change the injector and continued leak the 3rd. when i change the seals tha problem sold good.......................have a good repaire.

Posted on Jan 06, 2009

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.


    An expert whose answer got voted for 500 times.

  • Master
  • 2,336 Answers

Check the compression on #1 and possibly a leaky #1 injector. What fouling, I'm guessing carbon(black plug). If it's oil you will need to do a leak down compression check this will tell you if it's rings or valves. If you suspect a leaky injector (as I do) swap it with #4 (30 min job) and see if #4 plug becomes fouled

Posted on Nov 20, 2008

Add Your Answer

Uploading: 0%


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



Related Questions:

1 Answer

Where is the coolant fan switch located for a 2006 honda sabre

Hi, Ron for this scenario you will need your service/owners manual if you can't find the first and best tool you ever bought for your Honda, despair not, for a mere $0 you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
Radiator FAN Not Coming On
Magna Fan switch test flv
Honda VT1100C2 Owner Manual

Jul 20, 2016 | Honda Motorcycles

1 Answer

My yz 85 had oil poured straight into the gas tank now won't run or crank what can it be ?

Hi, Mark and the usual suspects are:
1. Fuel tank empty.
2. Fuel supply valve/petcock turned off.
3. Fouled spark plugs.
4. Engine flooded as a result of overuse of the enricher.
5. Vacuum hose to the fuel supply valve/petcock disconnected, broken, cracked, or pinched.
6. Fuel valve/petcock or filter clogged.
7. Discharged battery, check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
8. Loose or corroded wire connection at the coil, battery or plug between ignition sensor and module.
9. Spark plug cables in bad condition and shorting, cable connections loose, or connected to the wrong cylinders.
10. Ignition timing incorrect due to a faulty ignition coil, ignition module or sensors (MAP, CMP, CKP, O2 and/or BAS).
11. Security alarm needs a reset.
For more information about your issue, please visit the websites below. Good luck and have a nice day.

Nov 22, 2015 | GAS Motorcycles

1 Answer

Where to hook kickstand spring?

here is link to full workshop manual to download FREE
I also have leather waistcoat with loads vulcan riders patches n badges in thick leather if ya interested email or 07770070446...other sites for manuals but various years below...i have kwak gt750 but have tons of other links for whatever ya need bud...ride like ya stole it bud :)


Sep 02, 2015 | kawasaki VN 1500 Vulcan Meanstreak...

1 Answer

Why does my 04 yamaha r6 keeps fouling plugs

Hi, Anonymous and the usual suspects are:
1. Fuel mixture too rich or enrichner left out too long.
2. Incorrect spark plugs for your kind of service.
3. Piston rings badly worn or broken.
4. Valve guides are badly worn and/or seals worn, crushed or have come off valve guide and pump oil through it.
5. Spark plug cable weak or ignition coil faulty.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
Still having problems fouled spark plugs
What does fouled spark plug sound like Yamaha R1 Forum YZF R1 Forums
2003 2004 Yamaha YZF R6 Service Manual R6 Moto Data Project
OEM parts for Yamaha

Mar 21, 2012 | 2004 Yamaha YZF-R6

1 Answer

85 yamaha maxim xj700 carbon fouls pluges 1and 4 in 10 min.

if there oil fouled then rings or valve guides are bad from age--if gas fouled then the carbs need ajust or spark is bad--getta clymer manual

Dec 13, 2011 | 1982 Yamaha XJ 650

1 Answer

My 04 harley night train keeps fouling plugs left and right i richened the mixture with a 52 pilot jet. ran fine for awhile then fouled again could this be an electrical problem?

A #52 pilot is a bit on the rich side in my opinion. I usually use either a #48 or a #50 but each machine is a bit different and your location effects it as well. I wouldn't think an electical problem is the cause or you'd notice erratic engine performance prior to the plugs fouling such as misfiring, coughing or spitting back through the carb. How long are you running the enricher when cold starting the engine? This is the biggest reason I see for fouling plugs. People will start the engine with the enricher and allow the engine to run while they put their riding gear on, sometimes five minutes at full enrichement. This will foul the plugs quickly. The enricher uses a different fuel circuit than the normal running operation uses. It draws fuel directly from the float bowl and it's a very rich mixture. Try starting the bike with the enricher and once you can keep the engine running with the throttle, turn the enricher off. Use the throttle tension knob underneath the throttle to hold the throttle open enough to keep the engine running until it warms up.

Good Luck

Sep 03, 2011 | Harley Davidson FXSTB Night Train...

1 Answer

I've recently had a problem with getting my bike started, i have managed to get it to start now, but it can only be started with the choke fully open and if i try to close the choke it cuts out. (Even when...

It is most likely fouled spark plugs. You can take them out and sand blast them, or buy new ones.
I had a CBR 954, and noticed that the spark plugs fouled out pretty easily because it runs so rich at startup (and I would shut it down during the 'warm up' phase).
Here is some more information for you:
What are signs or symptoms that spark plugs in a motorcycle need to be changed?
There are several things that could hint at bad plugs.

- Hard starting.
- Slight to severe hesitation when you give the bike some throttle.
- Stalling, especially when you give the throttle a good twist
- uneven idling (tends to zoom up, or down, or sputters)
- After running the bike for a little bit, take out one of the plugs. If the end of the plug is wet, its not firing, and it could be oil fouling the plug
- take a look at the color of the end of the plug -- if it is white, its running too hot, and it can cause misfires
- look at the same area, and if it is covered in black soot, it can be poor gas mixture and dirt in your tank causing it to foul
Hope this helps.

Mar 13, 2011 | CCM RC 30 Motorcycles

2 Answers

What spark plug should i run in my 2003 YZ 125?

Run a B9ES if you don't have a problem with fouling. If you do have a problem fouling, run a B8ES. Both of these plugs are available at auto parts stores for a few bucks each.

The stock plug was a BR9** - the R indicates a resistor plug which is not needed.


Jun 18, 2010 | 2003 Yamaha YZ 125

1 Answer

Took the plastics off my 85 honda vf700s and sprayed of the bike at the car wash. Now it runs but it is missing alot of power

probably got water in the spark plug wells, the wells are very deep and the plug wir tends to restrict the water from boiling out. Try pulling all the plug wires off the plugs( one at a time if you need to) and blow down in the wells with compressed air to dry it out. You may also need to replace the plugs as the low power spark may have allowed them to become fouled with fuel.

Mar 12, 2010 | 1985 Honda VF 1100 Sabre

1 Answer

Hallo I have a problem can´t get lower than 2000rpm the probably an leak in intake but the engine rev´s it self from 3000-4500 and it it seems to cut there if i am in a corner then i...

You are corect. an air leak between the carb and the cylinder is the problem. It is possible a bad head gasket could let in air also.

A “very helpful” rating on this answer? Thanks!

Jul 02, 2009 | 1984 Suzuki XN 85 Turbo

Not finding what you are looking for?
1985 Suzuki XN 85 Turbo Logo

Related Topics:

309 people viewed this question

Ask a Question

Usually answered in minutes!

Top Suzuki Experts


Level 3 Expert

61168 Answers

Arnie Burke
Arnie Burke

Level 3 Expert

4481 Answers

Ed Nelson
Ed Nelson

Level 2 Expert

149 Answers

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

Answer questions

Manuals & User Guides