Despite having a mania for having other bikes dynoed I've never bothered with my XT,it came with Akra's on it and nothing else,I fitted a K+N and then a DNA2 still with nothing done to the fuelling I could tell it was running lean just by the feel but short of riding down the motorway on the stop for 20 miles ran good enough.

Sent for Kev's fuel mod and it was obviously blowing more fuel in made a world of difference and I see no reason for you not to do the same,how much is the mod now? but expensive it ain't and a 2 minute job to fit just takes a few runs on the road to try different ajustments and it's a good'un.

What you have to make your mind up about are you in it for the long haul and a PC etc or not as the case may be and go for a Kev mod.

I've tried both a PC with the above and the snorkel out ran even better but the icing on the cake are the holes in the airbox .

I won't comment too much on your post you seem a little frazzled but you can sort an XT out for far less than the crazy prices your quoting

Thanks for the advice. Apparently the tech is waiting for advice back from Dynojet so I still don't even know whether the AIS was blocked.

The reason for my "frazzled" state, which I do confess to :) is that having done a highlands tour a few weeks ago on my K1300S, I'm heading back on a trip to the Isle of Skye 2 weeks from today on the XT to see whether I can sell the K13. With an estimated 1500 miles in the week, including 600 miles of motorway, I could have done without the tech's advice of "I wouldn't take it that distance with the A/F like that". I don't claim any real technical knowledge so I rely on others for advice. When I'm close to skint and someone tells me by bike will be damaged by the trip I have booked a few days away, I feel frazzled. :)

Fingers crossed it will prove it be an error on the tech's part, or easily resolved by Kev's technical wizardry. :)

The AIS mainly runs below 5500RPM at any throttle opening as it does not affect the combustion A/F ratio, it is there to burn off the hydro carbons after the exhaust valve for emission control & as you now know will affect the A/F ratio reading down stream of the exhaust valve.

Why on earth would the Dyno tuner need to contact Dynojet, very strange statement from him. If he had blocked off the AIS he would have said straight away yes it was blocked off. I have spent many hours on the Dyno with these XT660 & have only seen that type of leanness when the AIS is not blocked off.

I called the dealership this morning and was told that the bloke's gone off to collect a bike, but is still waiting to hear from Dynojet.

I said "All I want right now is a simple 'Yes I blocked it' or 'No I didn't'" so I can stop worrying and throw those graphs in the bin.

Apparently they're aware of AIS-type system and usually clamp the pipes. Fine, but that still doesn't tell me whether they thought to do it on mine.

Very frustrating.

Thanks again for the help, Kev.

The bottom line you've been 'HAD' I have a bit(lot) to do with bike trade I see dozens of bikes K+N's open pipes they(punters) wouldn't know any of the fuel mods or a PC so long as they've got a hole in their back side never mind an engine map or changing oil this side of 20,000 miles!!!,and they all keep running like Swiss watches.

But when the panic subsides let me know what you need I'll loan you snorkel etc till you can get one,you'll be coming past my house going to Jockland junction 7 M6 we can even talk k12/300's!!,I thought I'd seen you name else where.

Thanks mate, I appreciate it. I'll see how things go over the next couple of weeks.

Well the tech that did the dyno run finally called back. Not that I'm any the wiser.

He says, "The AIS is just a form of pair valve. Not disconnecting the pair valve isn't essesential. It WILL be lean at the very start, but only for the first few rpm. Your XT was lean for 2000rpm. That's not because of the pair valve. If it had a lean blip at the start I would ignore it, but yours doesn't - it's lean for half the rev range. The guy at Dynojet also says that in the case of these bikes, the O2 Optimizer is as important or more so than the map."

So, he reckons it's lean for too long to be the AIS. I have no idea. I asked him about part throttle graphs, and he said that they do part throttle as part of the full mapping process, but not for a simple A/F ratio run. Again, I don't know if this is important.

End result - I am discarding the dyno results as I don't know enough to interpret then. The dyno bloke, and the guy from Dynojet apaprently, claim it is not essential to bloke the AIS, and that the AIS is not behind my lean graph. Kev, who I respect, says that's not true. All I know is that I'm �35 lighter and don't have a clue whether I have an issue or not.

For my next bike, I am going to check the forums first to make sure that no ****** mods it at all!! :)

Hamslay, see my recent post 'Kev Mod feedback'. I fitted the mod the other day and where the bike was feeling very lean for the first half of the rev range, it now feels completely normal. It's also adjustable, so you can tinker with the settings until you get the mixture you like/need. I assume the mixture is enrichened all the way through, but there are certainly no ill effects at half-throttle and up. It runs like a champ at all revs now. Perhaps the map is more sensitive to air temperature (which is the parameter being altered) at lower revs in any case?

It comes to just over 45GBP, and 20 minutes to fit, so to me if you have a long trip coming up it's a no-brainer. Your engine will be safe, even if it might use a bit more fuel. I'm 99% satisfied with my setup now (still have some final trimming to do), and wouldn't consider paying 300+ for a PC.

Just my €0.02.

(ETA: the mod comes with a block-type connector which works fine, but if you prefer a non-DIY appearance, you can always solder the device into the wires and heatshrink to finish it off. That's what I plan to do when I get a minute.)

OK. I just bit the bullet and ordered Kev's mods on ebay. Fingers crossed they turn up quick enough for me to fit at least the O2 controller before the trip. I tried to contact the forum member in the UK that was meant to have an unwanted controller but he didn't reply. Shame.

Dyno run brings bad news
 

Regardless of whether or not you ever get to the bottom of AIS/dyno run mystery, you WILL notice a big difference with the O2 controller - it is money well spent.




Sent from my iPhone using Tapatalk 2