Good evening fellow CBR owners.

I need some help locating the problem i have with starting my bike.

I've left my cbr outside under the roof these last 3 cold Norwegian winter months(I bought it from a guy who had a garage). and a couple of days ago i tried starting it and it did, and me being a total retard i only gave it around 2 min to warm up before gently rewing it a little bit, this led to loud "boom" sounds and it died out and it did start again, but it would act the same. so i thought i would leave it be and let my brother look at it.

And today i wouldn't start properly, we had to run and pop it in gear and it started like one of the 100 times we tried. and when it did and we rewed it, it would die out. we tried connecting the battery to a car but that didn't help much.

My brother believes the plugs might be blown.

And i was wondering if you guys had any input before i change the plug, and maybe someone have e "how to guide" for that?

Best regards

Firesnake

 

Firesnake, välkommen till forumet. Svensk här. I am also troubleshooting starter problems from a noob perspective and could post any findings in your thread if you would like. I actually managed to drive like 800 meters from the garage before it died on me so I am now checking everything from kinks in the fuel lines to what I suspect, old petrol. I also had to recharge the battery as it was really week. Good luck!

 

Welcome first off... plugs aren't difficult to change at all. A little challenging to get to the first time but not out of the novices capabilities. Do you have the service manual? It will be a big help along your way. Are your fairings on or off? If they are off its real easy to change them, if not, no worries, just a little more time consuming.
Checking fuel flow to the carbs is free so check that and pull the plugs to see how they look. That will at least get you headed in the right direction.

Don't be afraid to ask any questions you have. Most here are happy to help.

 

new fuel if you havn't yet. possibly change the oil. clean the carbs for sure. relatively easy stuff.

 

Thanks for the reply.

I tok the fairings off today, im aiming for a old school streetfighter look

I didnt have much time left over when i was trying to get the plugs out. And im wondering if the best approach to getting them out would be to remove the radiator? I have the book for the cbr f2 and f3 but i dont have access to it right now.

 

You don't have to remove the radiator. If your trying to make acess easy, you can remove the tank and airbox with just a few bolts. Less mess less headache. Plus you can stand directly over the plugs.

 

Thanks for your help Gtcole

Unfortunately my bike is in my moms garage and I'm working in another town, so i wont be able to check the plugs for at least another month.

I will keep you updated with the results

 

+1 on the airbox removal. Either that or have long skinny hands with knuckles of steel. The stock plug socket still works the best for me with a 10mm extended open end wrench. I also unbolted the coils and removed the rubber air intake seal piece for even more room. I was removing the valve cover to touch up a testarossa type paint job.

 

When this happened to me, people told me I may need to change my plugs. So I did. During the process of changing them, I discovered one of the plug wires had come almost completely off the spark plug. So it wasn't the plugs, so much as a loose plug wire. The loud BOOM you hear is probably from gas getting pumped into the chambers that isn't burning like it should. It accumulates and ignites all at once, hence the backfiring. But anyways sounds like a simple problem. either gas or spark. I would check to make sure all the wires are snug on the plugs, push firmly so they are ALL the way down, seated on the plug. If that doesn't fix it, I would change the plugs and the wires if that doesn't fix the problem. Good luck!

 

Thanks for the replies guys. will change the plugs next month when i get home, and i will keep you updated.