hesitates-chokes @ 2200 rpm

[luccaRSA]

HI all,

I've seen similar tread somewhere before, but no solution for it.
Please don't kill me for repeating.
So here is comes...
In a heavy traffic, (Johannesburg is hectic) at steady throttle around 2200 rpm (1st, 2nd and 3rd gear) my baby starts to choke or hesitate. It feels like there is not enough petrol or coil is not feeding enough juice. On the 2nd gear at that rpm I am cruising around 30-35 Km/h. Above that range (from 2500 rpm) she runs smooth all the way to 10700 – no issues. I changed spark plugs (OEM), new battery, air filter, Oil – Motul 10W40 semi synthetic, did dyno, even swapped to 95-octane and nothing. I don’t ride usually at that rpm, but I can’t keep it in 1st for 5 km just to avoid choking in hectic traffic.
Please help me, don’t know what else to check.
Std engine, 20000km, 2005 model, no power commander, exhaust looks homemade (middle part 2-1 piece) except slip-on which is stealth. Your input will be appriciated. Thx in advance. lease:

 

[Warputer]

I figured that was normal ....around 2K rpms or less, mine wants to choke and buck.

 

[Busman03]

I own an 03 Busa in stock form. I've had problems with my bike hesitating, or missing. It occurs at almost any speed, but precisely just off neutral throttle. I did some research in the factory manual and ran some tests with a multimeter and found that the secondary coil resistance, in my #4 cylinders ignition coil and cap assembly, didn't register anything. I ordered another coil and cap assembly and should have it installed this coming week. I will let you knoew what the outcome is.
I use my factory manual a lot, primarily because I'm too cheap to pay someone to do what I can learn to do myself. I've learn an enormous amount. If you don't already own a factory manual, it is well worth the expense, if you are at all mechanically inclined.
If I can find this thread once I've installed the assembly and ascertained it's affect, I will reply and let you know the results. I hope I don't sound like I'm just telling you my problems. There are so many variables involved. Working on motorcycles these days is so much different than 20 years ago, and I am only a back yard mechanic.

 

[YZ125]

My 02 had the same problem, I think all busas have hesitation and low speed stumbling. I made a switchable tre for mine and now have no problems at low speed the bike comes alive at any lower rpm situation, in town traffic is much more pleasant to ride in now. The tre makes your bike run in the 5th gear map through all the gears, bypassing the top speed restricition and smoothing out the low speed running, some do not like it, but it made a big diffrence for the better on my bike. By the way, You modded your stock header just how I wanted to do mine. I made 1 3/4" perforated race baffles and it sounds great, but should have ditched the left can and welded in a 2 into 1 merge collector on the header, if its not to much trouble pics or information of your exhaust would be appreciated

 

[BigDiesel]

pull your plugs again FIRST-before anything else...easiest way to tell if your motor is the culprit, or not-in which case you can start looking at elec. issues like coils n plug wires (mebbe a good time to eye them up good when pulling plugs again).

good luck

 

[luccaRSA]

Thank you all for your input.
I shall check coil as pointed. I am pretty sure spark plugs and cables are ok - just have been changed.
Now - about that coil... is there 1 or 2 coils and which one I should check or raplace. Bike has 20000 on it and she is 4 yrs old. Do you think coil will give up after 4 yrs?

 

[BusaWizard]

Busa's have coil over plug, there's a coil for each plug.

 

[luccaRSA]

surely that will make my life easier
You know, maybe I just gonna replace all those coils and that should sort out my problem

 

[mike1180]

I had the same problem on my 06.
Here we go..... believe it or not a TRE fixed it.
Mine ran terrible up to about 2800 rpm, until I added the TRE.
Now runs nice and smooth.

 

[luccaRSA]

I had the same problem on my 06.
Here we go..... believe it or not a TRE fixed it.
Mine ran terrible up to about 2800 rpm, until I added the TRE.
Now runs nice and smooth.

I don't know how tre works. I now has something to do with mapping and restrictions, but that's about it.
If I fit tre and connect it to whatever much be connected too, will that change mapping as well or I must do it myself?

 

[mike1180]

A TRE (Timing Retard Eliminator) is a touchy subject on here.
I guess about 50% love them and 50% don't see any use for them.
A TRE simply allows the engine timing to think it is in another gear, all the time.
Mine, as most, is in 5th gear.
This removes the top speed restriction that factory 6th gear has (and that I am not really interested in) but also removes all the Timing Retardation in the lower gears, and lower RPM’s.
It is a plug and play part, so if you don't like it, you can just take it out.
Some say it does nothing, but some say as I do that it levels out the jerky, jumpy lack of power that you describe.
My bike ran like crap from new until I put one on so I am sold.
My recommendation is to try one – they are not much money, and see what it does for you. There are lots of different kinds out there.
I got mine here and he has a good explanation of how it works:

Ivan's Performance Products

Do a search and see what others have to say. It is a controversial topic on here.
It doesn't have anything to do with fuel or fuel mapping so you can leave the bike stock or go to a Power Commander etc. if you like.

 

[mike1180]

Removed double post

 

[Mr Bogus]

I try to keep the tach over about 3G in anything above 2nd gear.. not a big fan of lugging a motor down.. could be the throttle bodies just need sync'd

 

[luccaRSA]

thank you all.
I shall do TB sync and then get TRE with gear indicator. I hope those gadgets will help.

 

[mike1180]

I would bet on it if I were a betting man.
Come back and let us know how they worked.

 

[YZ125]

The TRE does work, I did a steady running test in second gear at around 2,500 rpm with the TRE switched on, turned it off and the bike slows down, back on & the bike picks up rpm were it left off. You notice immediate diffrence when leaving from a stop in traffic. I know there are other ways to address the issue but for the price & ease of install it works. I have a Ivans original tre, I only made it switchable because I have an 02 and thought I could reduce starter kick back with it switched off, but it really did'nt mater, bike kicks back anyway, an 03 on starter assymbly is what it needs. The tre is nothing more than a 15K resistor that bypasses the gear position sensor making the ecu think that its in 5th gear all the time. Years ago I made one for my 98 TL1000R when all this was new.

 

[Wag]

A friend of mine had an '02 with a TRE installed but when he let me tool around on it, it didn't make a bit of difference. My '03 was smoother.

I've never had that hesitation you're talking about EXCEPT with dirty fuel system issues. Two treatments with Sea Foam took care of it. Eventually, I'll need to actually clean the injectors but for now, it's working just fine.

Also, run 87 octane in your bike. The Gen I doesn't run better with any higher octane. Don't go lower, though. In my area, they have 86 and 88 octane and I have to go to the 88 to get good running on the Busa.

The TB synch can never hurt. Make sure you use the right plugs, too.

Good luck.

--Wag--

 

[luccaRSA]

Plugs are stock. as far as octane go, we don’t have lower then 93-octane here in South Africa, so I have a choice of 93-octane or V-Power which guarantees not less than 95-octane.
I will do TB synch and injectors clean up at the next service, which is in 2000km (week or so).
I shall let you guys know.

 

[Wag]

Another thing you might check is to be sure your vacuum lines are all connected in the right places and that there are no cracks in any of the hoses, etc.

It's unlikely, but as long as you're under there, might as well.

--Wag--

 

[ThatsMrGimp2U]

I had the same problem on my 06.
Here we go..... believe it or not a TRE fixed it.
Mine ran terrible up to about 2800 rpm, until I added the TRE.
Now runs nice and smooth.

+1

I had a similar problem in my 03, but it was third gear just shy of 3k. Bought a tre on ebay for 25 bucks and that fixed it.