Greetings everyone, I would really appreciate some help as I am wondering if I have missed something.
A few months ago I had my Carburettors balanced and for just a few short weeks everything seemed to be OK. I then started losing power above about 3500 RPM which I assumed was either a sparking or fuel problem. A few weeks later I dropped the bike at a junction and for just a few weeks the full power was back and then the fault repeated.
Following the advice on this forum, I identified that one of the Spark plug drain holes was blocked and cleared it. The bike ran well for a few days and then it started to lose power at the top end as before.
I have replaced the air filter, Plugs, and Fuel Filter. The fuel pump is working using the testing method on this forum (shorting across the fuel pump relay). The fuel pump relay is working. (turning the bike over with the fuel line disconnected).
I am assuming my next steps are to take off the carbs and check the jets but I am wondering if I am missing something basic as I checked and cleaned them less than a 1,000 miles ago.
Does anyone have any thoughts?
Lossing Power above 3500 RPM
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Bike...and Dennis
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Re: Lossing Power above 3500 RPM
Have you used Honda's method for checking the fuel pump? Is it a Honda pump or aftermarket guesswork?
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WingAdmin
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Re: Lossing Power above 3500 RPM
You are looking at fuel and spark for loss of power, but don't forget to also look at air - a clogged air filter (or other restriction) can cause this as well.
Here's the important question: if you're in neutral, does it bog down at 3500 RPM as well? Or only when you're actually riding, under load? Does it bog down at the same RPM in first gear as well as second and third, or does the RPM at which it bogs down depend on load? Does it happen at a lower RPM if you're going uphill or downhill?
Here's the important question: if you're in neutral, does it bog down at 3500 RPM as well? Or only when you're actually riding, under load? Does it bog down at the same RPM in first gear as well as second and third, or does the RPM at which it bogs down depend on load? Does it happen at a lower RPM if you're going uphill or downhill?
Re: Lossing Power above 3500 RPM
Thank you for the replies. The fuel pump is original and tested according to the manual. (Actual 600ml / min). The new filter looks about 1/3 full. The issue occurs in all gears when riding up/flat/down. It is less noticeable when stationary/on the centre stand. The clutch was replaced with new metal and friction plates about 500 miles ago and oil changed (mineral 10W40). There are no obvious issues with the air filter. Best Regards, Rob