light load surge finally nailed

[Norvin]

G"Day Fellers,
at last I have rid my 2000 busa of the annoying surge that has been in the bike for over 18 months and from 48k to 63k.
After trying an ECM that Vic motorcycle wreckers kindly hired me for a weekend ( which eliminated my own from being suspect) I decided to bypass the gear position switch with a TRE, the result was immediate - surge gone and drivability back to normal, The gps must have been throwing random resistances at the ecm and the ignition maps where going all over the place, no code would have shown as the voltages where within range but the computor would have had no idea which gear it was supposed to be in.
Lessons learnt here was that my local Suzuki dealer never had a f---ing clue what was going on and wasted over a grand as well as never completed one task without stuffing it up.
The other unfortunate fact was that about a year ago I went to buy a TRE but was talked out of it by the seller in Sydney because he thought there was no way the gps could cause surging?
Enough rambling, I just hope this info mar help someone else with similar problems and thanks again guys for all your offers and imputs,I hope to contribute to the posts more regularly now as I have shadowed the forum for several years.
Regards John White.

[Legend]

Thanks for the feedback, glad you ended up finding the problem!

Leonard.

[BUSGO]

That's great news for you and a lot of other people with simillar issues.
Thanks for adding the result and I hope your fix is final for you.
Please let us know if it your bike gets a relapse. Mine continued to get the surge even after the TRE was fitted.
I've been convinced that other fixes have worked before, only to find another cause further down the road but with all your testing, you may have finally nailed it, as you say.

It may well be that the GPS needs to be replaced on the early models as they age.

[BUSGO]

Worth a sticky for a lot of people.

[westman]

Great to hear you finaly fixed the problem,those hidden intermitant glitches are a nightmare. Now, whats a TRE, is it a part attached to an aftermarket gear indicator light ?

[BUSGO]

TRE = Timing Retard Eliminator.
It gets rid of the automatic timing retard built into the SUZUKI ignition computer.
On some models, including the Hayabusa, Suzuki have put a timing retard in the system between 1,000 and 4,000 rpm to make the bike a bit more docile in the 1st four gears.
On the models after 2000, it also restricts the top speed by fooling the computer into restricting the rev limiter to 10,000 rpm. This ensures that top speed doesn't go over about 295kph.

A simple TRE tells the computer that the gears are always in 5th so that the retard is gone and the speed limiter is disabled.

A SMART TRE also enables the computer to recognise when the bike is in neutral so that the idle speed is not interferred with.

A Hayabusa must idle at 1050rpm + or - 50rpm for the fuel system to work properly.

A GIPro is a Smart TRE that also has a gear indicator that you can mount on the dash to let you know what hear you are really in.

[Norvin]

Great to hear you finaly fixed the problem,those hidden intermitant glitches are a nightmare. Now, whats a TRE, is it a part attached to an aftermarket gear indicator light ?

TRE ( timing retard eliminator) is a little plug in resistor which tricks the bikes computor into thinking its in 5th gear at all times instead of retarding the ignition timing a bit in the lower gears to tame down power delivery, most people probably buy them because it also defeats the speed limiter on 01 to 07 bikes which is activated by 6th gear, yes som TRE"s come with a gear indicator but in my case I did not want to try this unit as it still runs through the gear position switch which was what I was trying to bypass as I suspected it was faulty and indeed it was.
Regards John.

[RaZ]

mm, well I have this problem as well.. but don't have a TRE - I do have a GPS mod instead telling the ECU its in 4th gear with 4th being the most powerful map on my ECU.... should I pull it & re-dyno tune it & see the result??

Oh - just re-read your post - thought you were saying the TRE was causing the problem - not a GPS... looks like I'll be pull my GPS then ay?? :)

Time to go off to PTR!

[kitmark]

Anyone know a vendor where I can get a SMART TRE from?

[BUSGO]

I suggest you just search Ebay for a SMART TRE.

[RaZ]

So GPS is normally plugged in to the ECU right? wanna know how I can remove it & if it will break my bike doing so?

[BUSGO]

Your ECU will not run without input from the GPS Raz.
At least, not without a substitute signal.
That is what a TRE provides.
A TRE is plugged into line from the GPS to the ECU to create a phantom signal.

[RaZ]

doh - mmm, by pass? dont want get shit off fleabay :( revert to stock?? haha

[Volvi]

if you dont have a gear indicator I highly recommend this unit, its a smart TRE to.
http://www.gi-pro.net/

Anyone know a vendor where I can get a SMART TRE from?

[RaZ]

http://www.amcmotorcycles.com/index1.htm...4669430017

Aussie reseller for it.. 189 - nice, I am guessing that would solve my problem as well?