Loss Of Power

[ormby]

Hi, hope someone can point me in the right direction, I,ve searched the forum and havn't seen an answer so forgive me if it's been asked before, my bike is a 1998 GSX750F
Went for a ride to my daughters this morning and after about an hour on the motorway the bike seemed to loose power and would not pull strongly and struggled to pass 70mph, acceleration was down on the normal roads then returning home after the bike had cooled a bit bike seemed ok for about 30 mins the power went again and struggled to get past 70 and on hills and then again poor acceleration on normal roads didn't seem to want to rev past 6000 revs, first longish ride since oil and filter change last week (Putoline Sport 4 10/40 oil and Suzuki filter) have checked plugs and all are dry and a good colour and air filter looks clean, thanks in advance Stew

[Kreylyn]

Hi, hope someone can point me in the right direction, I,ve searched the forum and havn't seen an answer so forgive me if it's been asked before, my bike is a 1998 GSX750F
Went for a ride to my daughters this morning and after about an hour on the motorway the bike seemed to loose power and would not pull strongly and struggled to pass 70mph, acceleration was down on the normal roads then returning home after the bike had cooled a bit bike seemed ok for about 30 mins the power went again and struggled to get past 70 and on hills and then again poor acceleration on normal roads didn't seem to want to rev past 6000 revs, first longish ride since oil and filter change last week (Putoline Sport 4 10/40 oil and Suzuki filter) have checked plugs and all are dry and a good colour and air filter looks clean, thanks in advance Stew

My first thought is you have a restricted fuel flow that is allowing the bowl fuel level to drop. It flows, just not fast enough.

Second thought is it's over heating... but I would think you would noticed that it is putting off a lot more heat than normal if it was.

Krey

[ormby]

Hi, thanks for your reply, didn't notice any overheating, not sure how I would check fuel flow, did notice when I tried to accelerate the bike power stutterd, (if that makes sense) would a carb balance check be worth doing? only had bike 12 months and don't know history, had only 8,000 on the clock and everything looks new been well looked after! only 9 miles between last two MOT's before I got it.

[Kreylyn]

Hi, thanks for your reply, didn't notice any overheating, not sure how I would check fuel flow, did notice when I tried to accelerate the bike power stutterd, (if that makes sense) would a carb balance check be worth doing? only had bike 12 months and don't know history, had only 8,000 on the clock and everything looks new been well looked after! only 9 miles between last two MOT's before I got it.

Check the petcock flows well by pulling the tank off the bike. put a temp line on the petcock to drain into a container. Use the vacuum line on the carbs and apply suction to the petcock. With suction applied, fold the line over to kink it. This should hold suction on the petcock for at least 1 full min. If it stops sooner or the flow isn't full... you have a petcock issue.

Check the fuel filter is not clogged and is fully clean.

Check the fuel line is not kinking.

Krey

[ormby]

Thanks I'll give that a try

Stew

[ormby]

Replaced fuel filter, checked petcock, cleaned out tank breather, went for test ride seemed ok for about 20 mile on motorway then there seemed to be a surge of power like something was clearing then power dropped and now stutters over 4000 rpm there is also a clicking noise, I'm a bit stuck now

[muffinman]

Carbs might need cleaning.

[ormby]

You prob right just trying to check everything first, Forgot to mention tank was full of muck which I drained and flushed!