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Find Local Riders / Anyone from UK North East?
« Last post by MrDonev on March 08, 2021, 11:17:45 AM »
Just got a ST7 and I am looking to meet fellow riders in the North East!
GV650 / Re: moving foot controls
« Last post by MrDonev on March 08, 2021, 10:54:51 AM »
I was also wondering the same thing. Brake pedal is fine, but the gear shifter needs a little tweaking. It's a bit hard to put my foot underneath it. Any luck with trying it on yours?
GT650 / Re: Gt 650 comet - 2004 brake upgrades and length of brake lines?
« Last post by krehlick on March 06, 2021, 11:29:51 PM »
I'll be testing mine soon, a 2007 gtr 650.
Upgraded the calipers with CBR's but I left the old brake lines. The goal was to do them as well but turned out that the ones I bought had an oil leak so I just put the old ones back.

Had to manufacture the plates for the calipers, but not a hard thing to do if you have some decent tools.
GT650 / Re: GT650 Coolant soup - head gasket job
« Last post by extermin8tor on March 05, 2021, 02:15:22 PM »
Ah okay - I understand what you mean. If I pull the water pump would I be able to see if it is faulty? Is it a seal/bearing that lets oil through? The parts manual isn't clear
GT650 / Re: GT650 Coolant soup - head gasket job
« Last post by HyosungPerformanceTuning on March 05, 2021, 01:45:39 PM »
Cometic = 3 x layers of steel.
Only way to blow a head gasket is to burn through a metal layer or stretch the head bolts.

Ive heard of water pumps going before.
Never a head gasket, unless boost is involved
GT650 / Re: GT650 Coolant soup - head gasket job
« Last post by extermin8tor on March 05, 2021, 03:09:50 AM »
Ahh really?
Should I just strip it down and check it. Are there seals that go bad?
I guess it saves me from rebuilding the engine lol.
I can't return the gaskets that are on the way.

When you say the gaskets are 'cometic' - what do you mean by that?
GT650 / Re: FI FAULT codes 0351 and 0352, gt650r [solved]
« Last post by GhostInTheHyo on March 04, 2021, 08:31:47 PM »
OKAY! found out what was wrong... and... I am an idiot.

TLDR: Immobilizer switch, even disconnected from power made noise or failed to mantain continuity on high rpms, I was so sure that it wasn't the problem that never even mention it.

Im an idiot :-[ I installed an immobilizer remote switch in the ignition cable. It worked fine.
I disconnected it to test if that generated the fault, and because even when unpowered from battery, the ignition cable bypass of the immobilizer circuit, was always closed/on/continuous so figured that this can't be the fault, because the circuit was always completed, so I didn't bother with cutting and welding the cable back as default, because it was going to be the same.... I believed that so much that not even mentioned it. fool.

but as you suggested to check the side stand sensor got me thinking about the immob internal switch......... :facepalm:
completly removed the bypass and restored the default ignition cable continuity....

Then went for a ride and push it full throttle many many times and no FI. worked perfectly high rpms all the way xD.

In retrospective makes all the sense now that the FI idicates both coils codes. As you said, intermitent power or noise due to ignition continuity created the fault.


So the melted cable wrap was only because the coil got hot and they were touching, it seems.

.....now im going to sell 2 new coils when they arrive :')

thanks very much for the help! :D :D :D

Will be using the high performance flashed ECU happily again now :D

PD: the spark plugs gaps were absolutely on spec. but found some marks of what I believe are carbon tracks on the rear boot. Im replacing them anyways for the ngk cr-1 ones soon.
GT650 / Re: FI FAULT codes 0351 and 0352, gt650r [not solved yet]
« Last post by HyosungPerformanceTuning on March 04, 2021, 06:20:51 AM »
Plugs will work fine with a gap of 0.7 to 0.9mm

Your coils get power from your main relay (so do your injectors). The sidestand / neutral interlock system cuts power to this circuit if triggered.
The coils are triggered to fire by the ecu signal.

So, things to try.
Sidestand switch Bridge out.
Main relay wiring condition.
Ecu plugs are clean and on tight.
Pin 1 in the black plug. (Coil trigger)
Pin 10 in the grey plug. (Coil trigger)
Correct gap in plugs
Correct plugs
Plug caps are located tightly.
Ht lead to plug cap is secured/screwed in tightly.
Check plug caps for hairline cracking
Coils mounted properly.
Clean earth points.
Coil connector plug is secure and wiring secure.
Check the loom for rub through and breaks.

Good luck

See how you go.
GT650 / Re: FI FAULT codes 0351 and 0352, gt650r [not solved yet]
« Last post by GhostInTheHyo on March 04, 2021, 03:10:55 AM »
Outside the box here....
The bike cuts power to the coils if the kickstand switch is activated when in gear.
Maybe the vibrations ate setting it off.
The side stand switch on these bikes fail often.
This may be a long shot, but,
Disconnect the SSS bridge the plug on the loom side.

Worth a try

gonna try it.

I just realized that did not check the spark plug gap... checked the gap in the old ones and one was out spec. Maybe that and weak coils contributed... well some fun for tomorrow, while waiting on the new coils to arrive.

Also I always had hesitant acceleration the first mins after starting the engine and sometimes when hot. I pin pointed this to the TPS sensor, and calibrated and fix most of the roughness. but still sometimes it misfires on startup cold idle, and pulling out from stops or low rpms, always thought its just how the bike was... but now Im thinking bad coil slowly dieing all along?  guess will know when the new ones are installed.
GT650 / Re: GT650 Coolant soup - head gasket job
« Last post by HyosungPerformanceTuning on March 03, 2021, 11:53:15 PM »
Extremely unlikely to be a head gasket.
They are cometic.

Most likely a water pump.