Hi all, got a problem I need some ideas on. My 630 had a cracked piston so a top end rebuild was done. It didn't start after that, got told the tps is faulty, replaced tps and still not starting.then was told ecu faulty, not saving its settings. Got a second hand ecu but the bike still doesn't start. I checked the basics, fuel pump priming, spark is there and the starter turns over. I can smell the fuel and it does pop every now and again. Battery is fine and I put fresh fuel in. I just does not want to start. I really dont know what else to check. Any ideas or suggestions will be greatly appreciated.
Double check valve timing, spark plug condition and all electrical connections you disconnected to do the top end. I confident you'll find the problem in one of these areas. Good luck mate.
Check thread cant set timing correctly. I hope you did use stock piston,and check piston to valve clearance?
Start with the most basic things first. - Compression check. - Verify fuel pressure at the fuel rail. It's not enough to hear the pump, you could have a bad pressure regulator. Where are you located? Who is doing the work? What do you suspect caused the piston to crack? Good luck! .
Oldschool, Dynabob Ordered the cable for iBeat, should be here next week. The piston cracked (Cause unknown) and had it replaced by a mechanic who also did the valves and verified all was working. He claim the bike was running, although only for 5 min then would idle erratic, stall etc. He suspected a faulty TPS, which was replaced (Not calibrated in iBeat yet). This was installed but has not made a difference. I was told the ECU has gone bad and sourced a second hand one from France. It was installed but the bike wont start. Subsequently, i lost my temper with the mechanic, since i feel he doesn't really know what the problem is and i keep having to replace parts the whole time. I decided to take the bike back home and have since done the following - Tested TPS sensor on multi-meter - Tested OK - Tested pickup sensor (Crank sensor) - Tested OK - Tested for Spark- Tested OK - Spark plug very black and sooted up (Which leads me to believe the TPS is overfuelling). The plug was not wet at all. - Tested the Coil ( according to manual) - Tested fuel pressure - Test OK - Checked and tested all fuses and relays as per the manual - Replaced Fuel in Tank with fresh fuel - Check and cleaned every bloody connector Still the bike wont start, i am getting a compression tester to validate the compression (I seriously hope it is OK from that perspective) as well as perform a leak down test. I need to bet ibeat hooked up to calibrate the TPS and check for error codes. So far the neutral light is not flashing at all. I am smelling a strong fuel odour when attempting to start the bike, so i know that its getting fuel. Spark seems OK, i just think it has something to do with the ECU over fueling and not timing the spark correctly (At least i hope so, for my pockets sake) Thanks
Agreed, OBD2 cable ordered, incorrect one sent so exchanged it for the correct one and it should be here tomorrow. Done some more work to see if it could be something simple - Opened up throttle body and checked fuel injector for proper spray pattern - Tested OK, no problems - Used a USB bore camera to peek inside the combustion chamber, looks very good, no score marks or dents in piston - Very happy to see this - Tested fuel pump pressure - lots of pressure - no problem here Still need to pickup my compression tester from my Brothers house, should give feedback at the end of the week Cheers
Hi All so I think I found the issue. I got ibeat hooked up tonight and saw that the throttle position is showing as 93% WOT when I am not even touching the throttle. When I open the throttle to WOT, ibeat reads it at 0%. This is likely why it's not starting. No further errors reported in ibeat. I am swinging past the mechanic to pickup the original tps, which I suspect was never at fault. I ordered a replacement tps from ebay and I have read somewhere that they can work in reverse not sure if it's even worth trying to repair it.
I don't know if there's an issue with the TPS at all- it sounds to me as though all you'll need to do is use iBeat to reset/re calibrate the TPS. Now it's been quite a few years since I had my engine out (and all electricals disconnected, of course) and had to reset it myself. I recall that it did have to be done, and that it was simple to do.
Hi EricV. When i attempt to recalibrate the TPS its starting mv reading is around 4088mv. This is with the throttle closed. When i open the throttle it drops to 981mv at WOT. I was reading about these chinese TPS units that have their voltage reversed. It looks identical but they dont work. If i dont have any luck i will have to purchase a second hand unit from the UK.
Gotcha- I think. I say "I think" because, to be honest, electronics are not my forte at all, I'll be the first to admit. As you could tell I was thinking "hmmm, looks like the fella just needs to hook up iBeat again and reset the thing." Regarding finding the right TPS unit.... There was a thread a ways back that identified suitable TPS units from other makes (such as Yamaha.) Here's that thread, in case it's of any help in locating a TPS you can trust: http://www.cafehusky.com/threads/replacement-tps.34482/#post-550093
Someone else encountered this "reversed" problem. It seems Mikuni may make them both ways. I have a spare Husky sensor and one for a Suzuki or Yamaha and they look identical. Haven't got around to checking them with a meter though. Hopefully you've found the problem. .
Thanks Eric and Dynobob, yes i sat last night trying o figure out the problem with the reversed sensor polarity, and its not as simple as positive and negative. There is a 3rd wire in play which varies the voltage from 900mv (Average) to 4.x V. If i look at the wires and the diagram from the owners manual i see the following On the Sensor (Only related to TPS, not the Air or pressure sensor) Wire 3 - Black - Negative (For all 3) Wire 4 - Orange and Black ( Variable for only TPS) Wire 5 - Orange Positive (For both Pressure and TPS) The testing procedure for the TPS is as follows Connect voltmeter to Wire 3 (Black prong on Volt meter) and (Red prong) to Wire 4. The reading should be 900mv (Roughly). Then when you open the throttle the voltage climbs to roughly 4volt (Roughly). Now when i connect it to my YZF125 TPS i bought from ebay and i connect the wires up to test the results are as follows: Same connections as above, however the voltage starts at 4V and when you open the throttle it decreases!!! to 900MV at WOT. iBeat confirms this as the throttle is displaying WOT when it is meant to show 900mv However if i connect the voltmeter up as follows: Black prong to wire 4 and red prong to wire 5 then i get the same result as the testing procedure explains. So now i sit in a predicament, do i swap the wires around and risk losing an ECU due to short circuit or do i wait for my original TPS to come from the mechanic (Which i suspect was never faulty) or do i mess about and try and find the correct output to match the reversed polarity. Does anyone know if there is protection for the ECU in the form of a fuse incase something happens. I would rather replace a TPS then an ECU PS: i hate anything electrical, i i cant fix it with a hammer i cant fix it at all.
IT'S ALIVE !!. I installed the TPS I ordered and got het fired up last night. Been spending most of the day fine tuning everything. The battery took a bit of a knock with it not running for 6 months, guess I will have to order a new one. One thing I noticed, when I start it now I have to give it a bit of throttle and then it starts right up. The enricher lever does not seem to do much after the rebuild. I am convinced that it is a setting somewhere. I calibrated the tps voltage and got the idle at about 1800rpm. I know each bike if different but what are you guys running in terms of CO settings. Mine is at 100, 105, 107 Cheers
I would say that you need to check where it is rich and where lean. You should have lambda sensor already,and if not they are not expensive. Use multimeter or buy cheap afr meter. I first believed these over 100% values,but ended leaning way below 100 at full throttle(and in idle and mid too),after measuring real lambda value. Wideband afr meter is best tool but much more expensive,you can get to ballpark with narrow band also. I have stock air cleaner and gutted mufflers...Mufflers are definetly not restriction,mid pipe would be more of it if anything in exhaust is.
