Honda Rebel 250 in San Francisco

[BadgerBadger]

Had to replace my spark plugs in my Honda Rebel and I think it’s messed up the acceleration. It’s like the bike is just making noise after a certain amount of revs and not actually pumping anything into the engine. Would love to meet up with another Rebel 250 rider in the City to get a second opinion.
Is there anywhere else I should be posting?

 

[Darkness!]

Define

Had to replace my spark plugs

Why did you need to replace them and did you inspect the ones that were in the bike (if they were present)? What did the plugs look like? Specifically, what color were the plugs you pulled out? Whitish, dark, wet (either oil or fuel or both)? We need more info...

These types of questions will get more traction in the Garage section. Mods?

 

[HadesOmega]

Did you make sure the plug gap was right? You tightened it down till it seated and tightened it a little more right? New sparkplugs have a crush washer.

Did you inspect the plug cap also? Those wear out too.

 

[TwoWheelsRule]

not sure on the rebel, but on my KLR i need to remove the tank to access the plug. If you did, make sure you didn't kink a fuel line, or pinch a vacuum line or anything else.

 

[BadgerBadger]

Define
Why did you need to replace them and did you inspect the ones that were in the bike (if they were present)? What did the plugs look like? Specifically, what color were the plugs you pulled out? Whitish, dark, wet (either oil or fuel or both)? We need more info...

These types of questions will get more traction in the Garage section. Mods?

Thanks Darkness! Unfortunately the replacement wasn’t my choice. They were stolen out of my bike as I have to street park. They snapped one off though so I took it to the garage to extract as I didn’t want any shavings getting into the engine so I’ve gotta assume the garage would have put the new ones in properly. I changed them out again today myself because the issue seems to have been since getting new spark plugs but that hasn’t made a difference. The new spark plugs were black at the end, like charred from being burnt?
Will move to the Garage thread if I can’t find anyone on here that’s local to me. I’ve only had it just over a month so was hoping to find a more experienced rider who could tell me what it feels like to them.

 

[BadgerBadger]

Did you make sure the plug gap was right? You tightened it down till it seated and tightened it a little more right? New sparkplugs have a crush washer.

Did you inspect the plug cap also? Those wear out too.

I had it done in a garage because the originals were stolen but one had snapped in the engine. The garage put the new ones in so I assumed they’d done the job properly. I did change them out today to check if that was the issue but maybe I didn’t do it properly. Will give it a more thorough look in the morning. Thanks for the response.

 

[Darkness!]

Thanks Darkness! Unfortunately the replacement wasn’t my choice. They were stolen out of my bike as I have to street park. They snapped one off though so I took it to the garage to extract as I didn’t want any shavings getting into the engine so I’ve gotta assume the garage would have put the new ones in properly. I changed them out again today myself because the issue seems to have been since getting new spark plugs but that hasn’t made a difference. The new spark plugs were black at the end, like charred from being burnt?
Will move to the Garage thread if I can’t find anyone on here that’s local to me. I’ve only had it just over a month so was hoping to find a more experienced rider who could tell me what it feels like to them.

Ah. Unfortunately common in the City as crackheads use the porcelain part of the plugs as a pipe. Black at the end usually means you're getting either too much fuel or not enough air. It's too bad the shop didn't show you or keep the original ones (they should have). I would take it back to the shop if I were you to have them just double check that no lines got pinched somewhere

 

[ScottRNelson]

Black at the end usually means you're getting either too much fuel or not enough air.

It would be interesting to see an explanation of how those are different.

 

[CDONA]

Two different causes with the same result?
Wrong heat range could also give you the same sooty plug

 

[bpw]

If the engine rpm goes up but the bike doesn't accelerate your clutch is slipping.

 

[Darkness!]

It would be interesting to see an explanation of how those are different.

California bikes run excessively lean already because of CARB regulations. Often, when doing a a carb clean or rebuild, you can shim the jet needle such that the venturi is pulling more fuel at idle (more vaccum, as the jet needle sits higher). You can, however, shim it too much, so that the bike bogs badly when given any throttle greater than idle. Too much fuel. Another common problem is if a float needle gets stuck open and just constantly floods the carburetor with too much fuel...

Conversely, you can turn a air mixture screw so far in that for a given stock pilot and main jet combo, you are running the bike way too rich on fuel with not enough air getting through the venturi which can result in the bike idling ok-ish (if you set the idle set screw to bring the rpm higher) but feel like a very slow/sluggish throttle response or maybe a hesitation or a flat spot between the idle, pilot and main jet circuits. Too little air.

In the first example, the plug would be much sootier than in the second example but could look similar to an unpracticed eye.

 

[auditude]

Ah. Unfortunately common in the City as crackheads use the porcelain part of the plugs as a pipe. Black at the end usually means you're getting either too much fuel or not enough air. It's too bad the shop didn't show you or keep the original ones (they should have). I would take it back to the shop if I were you to have them just double check that no lines got pinched somewhere

I’d contact the shop; they should’ve done some type of “shakedown” test upon completion of their work.

If the engine rpm goes up but the bike doesn't accelerate your clutch is slipping.

I’m not reading this symptom but maybe OP will clarify for us...

Also, if you hit up @lucytriple she’s in the city and has a shop. I don’t want to volunteer her time or expertise but, she’s good people and she has love for teh BARFs...