Hi guys, on my recent trip to Scotland we got caught up in some.really heavy rain, and my bike (2009 non abs tenere 31000 miles) started to run rough and missfire something rotten. Its used all year round for an average of 250 miles A week.

The misfire happens only when ive been on a steady throttle for around 30 seconds. And its usually between 3-4000 rpm. And only when wet. After yesterdays rain it started again it runs very well when dry.

Bike is fitted with both kev mods dna filter snorkel removed and open leo vince exhaust. Its been set up this way for 2 years and no problems with rain or river crossings.

My first thought was coil/ht lead joint So i blasted with WD at the roadside. Seemed to do the trick for maybe 10mins. But it got me wandering as too why it only happens on a.steady throttle. Ive whipped off the TP SENSOR and have checked the resistance as stated in the haynes book of lies, It climbs very linear. But reaches a maximum of 2.48 k ohms.when the book says it should 0-6 kohms mine is only 0-2.48

The max resistance in hanynes says 4-6
Mine is only 2.48
Could this be the cause? Are the values in haynes correct?


If i hold at say 65 on motorway if feels gutless and revs drop and it starts to miss, give it a handful and its off like a scalded cat.

All connectors and clean and dry inc reg/rec and tps. Coil is off to be waterproofed.

Any help and suggestions would be most.appreciated.

Max resistance when measured accross blue and black blue wire.


Thanks Jon

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To boldly go where no Tenere has gone before.

If you have the kev mods fitted I am pretty sure your resistance readings will be way out. I would have a word with kev.

I may have slipped up here, on re reading the haynes book of lies i didnt follow.thebinstructions and actually removed the tps to check the resistance, i shall re do it on the bike.

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To boldly go where no Tenere has gone before.

Definitely see if the coil is at fault first.

HT leakage is quite common on all the XTs in damp weather. It is usually the joint between the lead and the coil that causes problems. Once dried out seal that area with silicone grease. Try and avoid silicone/gasket compounds that set into a rubbery substance as they invariable crack/come adrift at the edges over time with the continual heating up/cooling down and actually make the situation worse by trapping moisture or sucking it in through capillary action.

Failing that, it could be the TPS breaking down. The track inside can/does wear away eventually, giving erratic resistance reading and weird misfire at certain rpm.

Here's an example of a very similar sounding problem to yours...

http://www.xt660.com/showthread.php?t=23102

Started off as a suspect coil because it only appeared to happen in damp weather, but ended up being the TPS.

Neither of Kev's mods affect the resistance measured at the TPS.

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Well i removed the coil and stripped everything down, clipped the ends of the ht lead back, cleaned regreased everything. Rode home in the rain and theres no change. Still rough,
I had read the thread pleiades suggested before hand. Which made me suspect the tps.

I have seen 2 on ebay. One is the part number that tom listed in the thread, which looks a little different to mine but looks like it will fit.

The other is listed for an xj1300 and looks identical too mine.

Im unsure which to get.

Cheers
Jon

__________________
To boldly go where no Tenere has gone before.

The actual part number for bike is: 3P6-85885-00

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I found that too. But the website listing it is selling it at a whopping �137
Not really an option unless i am 120% certsin that is causing the problem.

The one fitted to the Ten doesnt have any identifying marks on it. Not even mikuni in the casing like the one pictured.

In tripletoms listing he lists a different part number Yamaha part # 5PS-85885-01
This looks the same shape but is open on the rear where mine is sealed and he has a Tenere I think.

Ill post pics.

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To boldly go where no Tenere has gone before.

Yes, Tom has a Tenere. AFAIK, the part he fitted (with the different part number) worked and cured his problems.

I think a lot of Yamaha TPS units are the same size, shape and hole spacing, but the big thing I guess that you have to be wary of is - do they have the same resistance range?

How did the resistance reading go with the TPS removed?

I take it this is the one you've seen on ebay:

http://www.ebay.co.uk/itm/Genuine-Ya...item2a53bb9af9

I've done a bit of digging and apparently the 5PS-85885-01 part was superseded by the 3P6-85885-00 part. This explains why there are "old stock" 5PS-85885-01 available on ebay. The only new ones available are 5PS-85885-01 and cost �130. You should be OK with the ebay item.

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Well just been looking around the web and found someninfo that suggests the readings i have are correct for yamaha part number 3P6-85885-00

http://www.rswarrior.com/forums/11-f...s/90311?page=2

I am therefor at a loss :-(

This is the tps tripletom had the part number for.

And this is the one that looks identical


Both. Have different part numbers listed to the one listed for the tenere. Youd have thought they would all be the same to save manufacturing costs??

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To boldly go where no Tenere has gone before.

Sorry Pleiades i completely missed your post, thats correct thats the item i have seen on ebay. Ive done the resistance test with the tps on and off bike with exactly the same results as before.

Going off what was written on the forum page i posted, these are correct to the revised part number, and exactly the same as a new component someone measured on there.

However i still suspect it so have ordered that. And another coil from a 2004 600x (Im asuming coils will be the same on both models as they all have the same part number on AJ suttons website) as when i had that off to do the resistance tests i struggled to get an accurate result on the secondary winding. Also the spark was a poor dull orange.

Well see what happens.

Ill fit new coil first and test and then new tps and go from there :-)

__________________
To boldly go where no Tenere has gone before.