Spree Diagnosis

[XCScott]

I have a 1985 Honda Spree that runs, but does not run great. Acceleration is so slow that by the time I hit the top speed of 23 MPH!!!!!, I already have a line of cars behind me. Starts great cold but takes ~3 minutes of stuttering at 15 MPH to warm up. Requires almost full throttle to start it once it is warmed up. It struggles into the wind and hates hills even more (big hills = walking). Carb is cleaned, new plug, new air filter, and new belt. Clutch pads looked worn when I was replacing the belt. Is there anything I can check or do that would get my acceleration and to speed back up to somewhat normal? I am no engine or spree expert so any advice would be appreciated.

[Wheelman-111]

Greetings:

Since it runs at all, but performance is poor consider the basics. Remove the spark plug and have a look at it. Post a pic if you can. While the plug is out, find a Compresson Tester and measure. Remember to hold the carb Wide Open when you test. Let us know what that shows. Since you went to the trouble, why not spend $5 and try a new spark plug. Sometimes that's all it is. If not...

Removing the exhaust is a little daunting for a non-expert, but in the pipe may reside the problem - carbon build-up - if the compression test is good and the carb really is clean.

[patthesoundguy]

Make sure the plug is gaped properly as well. Did you set the idle airscrew and idle speed as per the manual? Those not being right can make it hard to start and sluggish. The compression test will really tell the tale though. If you have strangely high compression on a stock spree you may have a really shiny worn out cylinder. Does your slow takeoff get worse the longer you ride it in a go?

[Pete M]

Carbon in the exhaust port. Clean carefully.

[XCScott]

Finally got around to testing the compression and it was right around 97 so low. The spark plug looked to be oil fouled (pic). Idle airscrew and idle speed set per manual. I plan on removing and cleaning the muffler later.

[XCScott]

With a warmed up engine the compression is about 92-93.

[patthesoundguy]

That plug looks wet so you could totally have a plugged exhaust as Pete suggested causeing a super rich condition. Or the bystarter staying in the cold position. I also believe you have worn out rings and cylinder. I bet of you pull the head off and take a look the cylinder walls are shiny like a mirror, just a guess. Does it have slower takeoff when it warms up?

[XCScott]

The plug is wet/oily every time I remove it. Suggestions on the best way to "unplug" the exhaust? Just throw it on a fire and wait a while? I would say the acceleration is slightly slower when warmed up. It is hard to tell though since it sputters up to 15 when cold. I was planning on buying a BBK so that would take care of the possible worn rings/cylinder.

[Johnniespeed]

I have cooked six Spree, one Aero and one Gyro mufflers. I heat up my gas grill and place the muffler inside, with the inlet and outlet pipes protruding out the cover, about every ten or fifteen minutes I blow compressed air into the inlet or outlet until all smoking stops, you would not believe how much smoke ( oil ) will come out. Plan on at least an hour or more for cooking.
Then I sandblast the exterior and paint it.
Of the last 12 Sprees I have restored, I have found the engine sensitive to compression and intake system. The cylinders wear and need to be bored oversize, I wasted much time trying to fool myself into thinking I could hone the cylinders back to "good enough" , those efforts were a waste of my time and I will never hesitate to bore again. I have a local motorcycle shop who will bore the cylinder and machine hone to exact tolerance, chamfer all ports for only $45. I also found the air cleaner must be exactly the way the factory produced it, the filter must be in place, the lid gasket must be in place and the lid screw must be in place. Of course the carb must also be in perfect condition, once all these little things are right, the scooter will perform flawlessly and will be dependable.
All my stock Spree's do 28-32 MPH, so 23 sounds wrong to me.

[patthesoundguy]

I agree with Jonniespeed, if the cylinder is done bore it out or order this http://www.ebay.com/itm/Honda-Spree-NQ5 ... 59&vxp=mtr a great deal and has all of the parts you need.

[XCScott]

Just shined a flash light into the exhaust tip and I could physically see that it is clogged. Burning it this afternoon. Hopefully this cures my problems. Thanks for the help guys!

[patthesoundguy]

Just shined a flash light into the exhaust tip and I could physically see that it is clogged. Burning it this afternoon. Hopefully this cures my problems. Thanks for the help guys!

Got fingers crossed for ya. Sounds like the pipe bake will at least improve it of not solve your issues.

[XCScott]

Well now I feel like something is wrong with the amount of acceleration I have haha. Much better now, hit 30+ very quickly. Compression is just above 90 psi now? I hope its not running to lean or something. Either way thanks for the help!

[patthesoundguy]

90psi is very low. My stock spree motor I just built last night has over 125 psi