Slight power delivery type problems.

[Dave20046]

(...aside from the obvious 'it's an sv')
Just wondered if I could run this past the clever ones on here?
I've always had a bit of a power drop/'pull back' at aroun 6 or 7 k when revving hard in lower gears. This is a 1999 carb washer restricted naked sv with standard jetting and filter and full race system exhaust.
Recently the problems been amplified (or so it seems unless I've just been riding harder) for example the other day I was going round a tight bend in second around 4 or 5k revs (guessing but that's what it sounded like) then as the corner opened up I opening the throttle wide slipped into 3rd and cracked it right back again (still a bit leant over) the bike accepted it for the first second and appeared to accelerate as it should but then it hit a brick wall powerwise (unsettled the bike just a bit!) and then it reapplied itself after it's little cough and was normal. This has happened a few times I have a good idea everytime it's around the 6k rev mark - the acceleration just abruptly stops momentarily then carries on as usual.

The only thing that's changed recently is I fully serviced the bike and changed it's tyres, two things here that I'm considering are new (clean & clear!) air filter and the fact I've removed and reinstalled the backwheel -chain tension/wheel alignment?). Unless the restrictor kit could be causing the issue? ('I had to remove it officer it was ruining my bike')

[johnnyrod]

Its running lean. Little point setting it up on a dyno while restricted, but that's what is needed. It's the race pipe that's doing it. If it's a curvy then you can take the needles out of the sildes and put the little washer underneath to richen it a little (called shimming, when you have it in bits you'll see what I mean), but it will still be running lean at the top end.

[Dave20046]

Originally Posted by johnnyrod

Its running lean. Little point setting it up on a dyno while restricted, but that's what is needed. It's the race pipe that's doing it. If it's a curvy then you can take the needles out of the sildes and put the little washer underneath to richen it a little (called shimming, when you have it in bits you'll see what I mean), but it will still be running lean at the top end.

Cheers johnny. I did wonder if it was running lean but the plugs didn't look too lean so sort of put it to the back of my mind. Would bigger main jets help along with shimming?

I have stuff like that. Get the carbs balanced first

[Dave20046]

Originally Posted by Alpinestarhero

I have stuff like that. Get the carbs balanced first

cheers will do that first then see where I am. meant to do it last month but...well I'm lazy

I too would go with balancing the carbs before assuming it's running lean. Start off with the simple and easy stuff and work on from there. No need to strip the carbs down to shim when all is needed is carb balance.

[Dave20046]

Originally Posted by Stig_Of_The_Dump

I too would go with balancing the carbs before assuming it's running lean. Start off with the simple and easy stuff and work on from there. No need to strip the carbs down to shim when all is needed is carb balance.

Thanks guys, I'll get that done - it's done about 11k so probably about time for a balance . will update when balanced. (I take it it's advisable/required to remove the restrictor washers to balance properly.)

As said carb ballanced... Does sound like fuelling might also be an issue, but then it could also just be inpropper airflow due to restriction.

How long till you go full power?

Originally Posted by Dave20046

Thanks guys, I'll get that done - it's done about 11k so probably about time for a balance . will update when balanced. (I take it it's advisable/required to remove the restrictor washers to balance properly.)

my bike as done 18k in my hands...carbs never been looked at, apart from to put un / take out restrictors

[Dave20046]

Originally Posted by ThEGr33k

As said carb ballanced... Does sound like fuelling might also be an issue, but then it could also just be inpropper airflow due to restriction.

How long till you go full power?

About a year