Gen 1 Busa Hickups / Jerk on high rev. (Video Link below)

[GeekOnBusa]

I have a 2006 Busa, It Runs pretty smooth with no problems whatsoever except a sudden jerk, which feels and sounds like a sudden gear change it only happens when I rev hard. The bike is completely stock, No power commander, Only Yoshimura Slipons, Have 50k Kms on it. Engine head never opened, running stock pistons and valves.
I checked the injectors which are clean and fine, New battery, Not sure if the fuel pump is the issue, don't have anything to measure fuel pressure. I also suspect, My cam timing could be bit off.

Does anyone have a clue here? Please watch the video, at this link
If the video is not available download it from here

The issue can be observed between 22-25 seconds in the video you can hear a gear shift-like sound 2-3 times.

[Bumblebee]

The video froze for me...it might be my laptop however no other videos have been freezing....

Why do you think cam timing would be off if you've never opened the engine?

If it was off, the bike wouldn't run or wouldn't run very well at any rev range...

I suspect the fuel pump or fuel filter...have you ever changed the fuel filter?
Have you changed the spark plugs?
I would also check the coils, you might have one that is partially failing under load......

I'd also check your clutch which may be slipping under hard acceleration.....

What kind of oil are you using? Certain brands can cause slippage...

[GeekOnBusa]

The video froze for me...it might be my laptop however no other videos have been freezing....

Why do you think cam timing would be off if you've never opened the engine?

If it was off, the bike wouldn't run or wouldn't run very well at any rev range...

I suspect the fuel pump or fuel filter...have you ever changed the fuel filter?
Have you changed the spark plugs?
I would also check the coils, you might have one that is partially failing under load......

I'd also check your clutch which may be slipping under hard acceleration.....

What kind of oil are you using? Certain brands can cause slippage...

The engine head/block was never opened, Never serviced fuel pump, or replaced stainer, spark plugs are new using NGK Iridium plugs, Coils have been replaced 2 years back (It was giving FI light and 2 coils were blown) .
Also, I think my clutch is fine as it would not slip like that for a split second, and it doesn't happen every time. I using Motul 300V 15w-40 fully synthetic oil.
I think cam timing is off because my cam chain tensioner feels bit loose. Also, I see similar issues in this video of Brocks (From Brocks Performance)

[jwcfbd]

I use to have a 2001 and found out that my cam chain was off a tooth. You can see the before and after in my dyno run. They did a recall on it before I took delivery so I never noticed missing the missing HP but to me it ran great.
I was under the impression that you should not run a full synthetic on bikes with a wet clutch. I do however see where a lot of guys are but they're running mobil 1. Looking up Motul 300V it looks like it's a race oil with mixed reviews of running it on the street as a daily driver. How long have you been running this oil and how long has the bike had this issue?

[Busa Quick]

The fuel pump is fairly cheap compared to taking the engine apart, and it is very likely to be the problem.

You can swap the pump in a hour. Try that first.

[GeekOnBusa]

I use to have a 2001 and found out that my cam chain was off a tooth. You can see the before and after in my dyno run. They did a recall on it before I took delivery so I never noticed missing the missing HP but to me it ran great.
I was under the impression that you should not run a full synthetic on bikes with a wet clutch. I do however see where a lot of guys are but they're running mobil 1. Looking up Motul 300V it looks like it's a race oil with mixed reviews of running it on the street as a daily driver. How long have you been running this oil and how long has the bike had this issue?

View attachment 1689135

Thanks for this info, But i don't think so its the problem for me, I meant my timing chain could be loose or elongated. The power is reduced gradually over 15 years mostly because of a lack of valve maintenance and loss in engine compression.
However, I ran the engine flush liquids and injector cleaning fuel mix multiple times to get deposits. It did not fix the problem but I definitely saw improvement in engine idle and overall smoothness.
And I've been running this oil for many years, well before this problem arrived. But I'll try to change my engine oil as you said.

[GeekOnBusa]

The fuel pump is fairly cheap compared to taking the engine apart, and it is very likely to be the problem.

You can swap the pump in a hour. Try that first.

Yeah, Thanks for the heads up. I was going to do this anyway. because I feel my fuel pump makes a louder noise then usual when put to ignition. This could be a sign of an out pump.

[Bumblebee]

Yeah, Thanks for the heads up. I was going to do this anyway. because I feel my fuel pump makes a louder noise then usual when put to ignition. This could be a sign of an out pump.

Good luck with it.....having issues like this is never fun, nor is it simple and quick to diagnose and repair.

[202mphbusa]

The fuel pump is fairly cheap compared to taking the engine apart, and it is very likely to be the problem.

You can swap the pump in a hour. Try that first.

Compression test and leak down test will tell you a lot.
If you short shift to second gear at like 1500 Rpm Then smoothly roll the throttle WFO.
What does it do then ?

[Oz22]

Sounds electrical to me, a distinct sharp missing. If I couldn't find an obvious loose wire so to speak I'd be off to the shop to ask an expert. Why replace half the parts on your bike chasing a small problem? Reminds me of the "Cold Start stalling" thread, 4 pages, half the running gear replaced, and still the problem exists.

[Dustin02]

I can't view the video, but from the comments, it could possibly be a weak side stand spring which is allowing the stand to bounce a little causing the switch to act up which causes intermittent ignition dropouts. Could be very simple and a cheap fix.

[GeekOnBusa]

Sounds electrical to me, a distinct sharp missing. If I couldn't find an obvious loose wire so to speak I'd be off to the shop to ask an expert. Why replace half the parts on your bike chasing a small problem? Reminds me of the "Cold Start stalling" thread, 4 pages, half the running gear replaced, and still the problem exists.

@Oz22
I re-uploaded the video please check at
Night Ride.mp4 is available for download
Timestamp between 22-25 sec

[GeekOnBusa]

I can't view the video, but from the comments, it could possibly be a weak side stand spring which is allowing the stand to bounce a little causing the switch to act up which causes intermittent ignition dropouts. Could be very simple and a cheap fix.

@Dustin02
I re-uploaded the video please check at
Night Ride.mp4 is available for download
Timestamp between 22-25 sec

[GeekOnBusa]

Compression test and leak down test will tell you a lot.
If you short shift to second gear at like 1500 Rpm Then smoothly roll the throttle WFO.
What does it do then ?

Most likely I will get that jerk/hiccup as soon as I am on a higher rev range. I didn't try the same way you said, Speaking based on what I noticed while riding.

[BlueBacon]

Most likely I will get that jerk/hiccup as soon as I am on a higher rev range. I didn't try the same way you said, Speaking based on what I noticed while riding.

'03 with the same issue at 7k-ish RPM (full throttle-2nd gear). Near instantaneous jerk...as if the chain jumped a tooth, or clutch was tapped. Mine only does it once though. Mine also sounds really rough at idle...like a diesel and loud. I can hear my cam chain lightly clacking, but can't do anything with it unless I open her up. Most everyone here has told me the timing is off, or the transmission gears are going out.
I did the fuel filter bypass mod, replaced the oil line to the CCT, attempted to click the CCT ratchet further in, replaced clutch pack, added 3 HD clutch springs and the carpenter clutch lock ring.

[sixpack577]

'03 with the same issue at 7k-ish RPM (full throttle-2nd gear). Near instantaneous jerk...as if the chain jumped a tooth, or clutch was tapped. Mine only does it once though. Mine also sounds really rough at idle...like a diesel and loud. I can hear my cam chain lightly clacking, but can't do anything with it unless I open her up. Most everyone here has told me the timing is off, or the transmission gears are going out.
I did the fuel filter bypass mod, replaced the oil line to the CCT, attempted to click the CCT ratchet further in, replaced clutch pack, added 3 HD clutch springs and the carpenter clutch lock ring.

That is 2nd gear going out

[GIXERHP]

That is 2nd gear going out

Agreed!

[BlueBacon]

That is 2nd gear going out

I've only pulled thru 2nd and 3rd, but it only "jumps" in 2nd gear...so I agree LOL
I'm almost at 44k miles...working up the courage to do a overhaul at 50k: transmission, timing chain, chain guides, head gasket, and clean 20+ years of gunk off the pistons. Can't afford racing mods so don't talk me into new cams, turbo, etc

[sixpack577]

I've only pulled thru 2nd and 3rd, but it only "jumps" in 2nd gear...so I agree LOL
I'm almost at 44k miles...working up the courage to do a overhaul at 50k: transmission, timing chain, chain guides, head gasket, and clean 20+ years of gunk off the pistons. Can't afford racing mods so don't talk me into new cams, turbo, etc

The transmission issue sucks, period.
But, with a service manual, and everyone here to help, it isn't a bad job.
You only need a few special tools, a calibrated torque wrench, and a few basic hand tools.
Maybe have the block honed and get new rings, and new crank bearings, just because you're already in there.
As well as the timing chain, guides, and tensioner, you just need a gasket set and some seals.
50k miles would be a good time to check steering bearings, swingarm bearings, and wheel bearings too.
All may be fine, but if the engine is out, it's a good time to replace them, and none are expensive either.

[Oz22]

40k and a gear dying? Nasty. I hope they did a better job in the Gen-II transmissions. I remember the ZZR-11 I owned was supposedly renown for bent selector forks on 2nd gear, though I never had the issue myself. When I sold it the guy went up and down the street changing from 1st to second, over and over, so he was looking for it. A client I had owned one too, he was an old racer dude and they regularly changed gears without the clutch. I assume most of these issues arise from the bikes being flogged! Sure they can take it, for a while...