• Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

PU Kit - Factory Delivered Resistor Value (ohms)

S

SimpleOne

Husqvarna
AA Class
Hi all,

Should anyone out there have a 630 which they know has the factory Arrow ECU and PU resistor, could you confirm the resistance value of the PU resistor?

My bike when I got it second hand came with the twin arrow exhausts (and supposedly, the matching ecu, but I know of no way to verify that). At the time I checked it had a PU resistor in place, which it did across the Green/Red and Brown/White, all nicely heat shrink wrapped with the seals in the back of the connector, certainly didn't look like a poorly done DIY or anything. So, I never gave it a second thought and didn't check it's value.

Today, I pulled the plug to measure the resistor value for a mate that was looking at second hand Huskies, just in case it didn't come with said resistor and he wanted to do it. I know from prior reading that people say it should come in at 2200 ohm.

Mine measures at 273 ohms, and is marked as 270 ohm (5% tolerance) by its colour bands, and it looks rather large, I'm guessing half or even one watt, compared to the typical quarter watt that is normally suggested.

All my other reading, everyone says a 2200 ohm, 1/4 watt resistor is what's used. I've just whacked one together for my bike using a 2200 ohm 1/4 watt resistor, but I'm hesitant, in case the mythical 'Arrow ECU' required a different value from a standard ECU. Seems very unlikely to me, but, who knows. I find it hard to believe the previous owner went to all the trouble of such a neat DIY PU, and used entirely the wrong resistor value....:confused:

Thanks in advance if anyone can help out on this matter!
 
I installed the ECU and Arrows myself I know the ECU is legit.

Could you post some pictures so I know what I am looking for, then I can do the measures.
 
HuskyBrutha said:
I installed the ECU and Arrows myself I know the ECU is legit.

Could you post some pictures so I know what I am looking for, then I can do the measures.
Click to expand...


As per the images by Rotax, it's a terminating plug that goes onto the ends of the wires coming from the ECU that go to the factory O2 (Lambda) sensor. The resistor is connected to two of the pins in the white terminating plug (and then normally has black heat shrink over it) which connects across the Red/Green and Brown/White wires from the ECU. Normally the wire and associated plug is zip tied up to the frame, somewhere above the cylinder head (just under the tank).

Rotax_655, thanks mate. Your images are exactly what I would expect based on everything I've seen online. My DIY one is now reading 2195 ohms. Did your bike have the Twin arrows kit installed with that ECU?
The odds of it requiring a different value for the Arrow ECU seem really low, just can't quite fathom how someone went to the trouble of doing a neat DIY job using entirely the wrong value resistor. I guess anything is possible, the joys of second hand ownership :p
 
I am interested how did it work? Does it run well? When i tried mine without pu plug,it lost half of its power,no dream to raise front wheel with gas only. I dont know if resistor values are related to af values,or if it is just indicator for ecu to go race mode and be able to change af ratio.
 
Haven't put it back together yet. Quickly ran it just to see that nothing immediately fried, but have a batch of other maintenance bits I need to sort out whilst I have the tank and airbox off. I'll let you know what sort of difference it ends up making though. It might not be hugely noticeable for me since I have the PCV on there using the DynoJet FMF Q4 map, which is a bit richer than stock in the top end anyway. That said, it's leaner in the low/mid rpm and throttle openings, which is where most people seem to have commented that they noticed an improvement from the PU kit, so here's hoping it helps.

Will try running it with a zero PCV trim map and just see how it feels, then go back to playing with the PCV after that.
 
SimpleOne said:
As per the images by Rotax, it's a terminating plug that goes onto the ends of the wires coming from the ECU that go to the factory O2 (Lambda) sensor. The resistor is connected to two of the pins in the white terminating plug (and then normally has black heat shrink over it) which connects across the Red/Green and Brown/White wires from the ECU. Normally the wire and associated plug is zip tied up to the frame, somewhere above the cylinder head (just under the tank).

Rotax_655, thanks mate. Your images are exactly what I would expect based on everything I've seen online. My DIY one is now reading 2195 ohms. Did your bike have the Twin arrows kit installed with that ECU?
The odds of it requiring a different value for the Arrow ECU seem really low, just can't quite fathom how someone went to the trouble of doing a neat DIY job using entirely the wrong value resistor. I guess anything is possible, the joys of second hand ownership :p
Click to expand...



My TE is in the original exhaust configuration with a European ECU code 8000H1642. The only thing I changed after removing the lambda probe and installing the PU plug is the mixture ratio via IBEAT which is now 96-98-98.
 
I've not got my iBeat settings to hand, but with the Arrow pipes and opened up air box you need higher numbers to compensate for the higher flow.
 
It depends. I have allso much lower values than stock 100-100-100,even lower than rotax. And gutted pipes+opened air box. It was way too rich at 100-100-100. Only way to fnd out what it wants is to measure it with lambda,preferably wide band but stock will get you in area too. I used old autometer af meter taped in mirror,much easier to ride while driving than multimeter...
These all over the place values make me think either ecu is learning,and then af value depends what it learned prior pu plug,or different ecus and values, (mine is eu too,so...) or something else. But either way,measure what it wants,and adjust accordingly.
 
You must log in or register to reply here.
Back
Top