Advice required.

[bagmaker]

Vacuum leak?

[Mincehead]

I had a set of worn dynojet needles in a bike I bought. I contacted Dynojet to see if I could just buy the needles rather than a kit. They asked me to return the needles and sent me a new pair FOC. Brilliant customer service.

FECK, never seen needles worn like that up by the clip grooves!
Click on the image on sadmansteves post (two back from this) folks to enlarge it.

[Mincehead]

Kenvis Repesco, it it was me I would go the Factory Pro route, their emulsion tubes are nickel plated and wear more slowly. Most folk seem to use stock Yamaha needles with them though as their own needles are notoriously hard to set up it seems.

[Kenvis Repesco]

Just been looking through some old receipts I was given and it seems my bike has the factory pro emulsion tubes fitted. That was in October 2008, but the chap I bought the TRX of did so few miles I would be surprised if they were worn out. I have the tel number for DJ so I will give them a ring tomorrow hopefully they will be able to help...the needles really are that bad. Thanks again chaps.

[Mincehead]

TRX`s with stock gearing and a lot of town riding tend to knock them out quickest, lugging the bike at lows revs is the worst thing for them.

[Con Rod]

Just been looking through some old receipts I was given and it seems my bike has the factory pro emulsion tubes fitted. That was in October 2008, but the chap I bought the TRX of did so few miles I would be surprised if they were worn out.....

It is easy enough to confirm if they are the factory pro pr stock tubes, just look down the bore of the carb and if the emulsion tube is silver then it is the factory pro one, if it is stock it will be brass.

If they are Factory Pro Tubes it is pretty unlikely they will be worn.

The stock needles would suffer more wear in the factory pro tubes than in the stock ones because the stock tubes are softer brass.

Stock needles can be had from Kedo for EUR12.50plus postage. This is a lot cheaper than the TI needles from factory pro (all be it they are stock, so stock jetting)

Interesting that you say you could smell petrol. Have you checked your float levels? If they are too high you would be running rich and depending on how high they are you could be spilling fuel. In my case the previous owner had the cloat level at 4mm below the line on one carb and 12mm above the line on the other. Suffice to say I was running rich on one side.

[Kenvis Repesco]

Thats inreresting that is. My bike does seem to produce a little Black smoke from the right pipe...not always. So could I use the stock needles in the Factory Pro emulsion tubes to no ill effect. Thanks David.

[Mincehead]

Yes, in fact that is the route most tend to go down. Your motor is stock yes? I seem to recall you having a K&N filter fitted but to a stock airbox?
TRX`s do tend to be a bit on the rich side on their carb settings that`s why aftermarket cans can be fitted without needing to worry about them upsetting the carburation too much.

[SDN]

I had a set of worn dynojet needles in a bike I bought. I contacted Dynojet to see if I could just buy the needles rather than a kit. They asked me to return the needles and sent me a new pair FOC. Brilliant customer service.

Mine went like that, replaced needles with Factory Pro Titanium and Emulsion tubes to match - problem sorted

[Kenvis Repesco]

I tried the TRX this morning after raising the circlip one notch, seems a little better but still has the stumble when the throttle is backed of and opened again. After I got back from my brief ride I took the existing DJ needles out and drove up to the DJ headquarters in Preston. I spoke to a fellow there called Richard who was obviously very knowledgeable. He looked at the needles and said there was some wear, mostly were the needles had been continuously emersed in fuel when the bike wasnt being used much. So he swapped my needles for some new improved jobies and new circlips. When I took out the apparently worn DJ needles they where set on the fourth clip down. Richard at DJ asked me what my set up was, Beowulf cans and K&N filter and said for that set up the circlip should be on the second from the top and mixture screws 2.5 turns out. My carbs are standard apart from the factory pro emulsion tubes, I think my main jet is 148. I havent tried my bike yet but I will tomorrow, and will let you know what its like.

[Kenvis Repesco]

Also forgot to mention before I inexplicably hit the return button. I have ordered some iridium plugs...maybe these will help, or maybe its just an act of shear desperation . One other strange symptom was at about 4-4500 revs the motor felt like it was holding back a bit. When the bike had the DJ kit fitted it was set up on a rolling road, and I am sure the technicians wouldnt have let the bike be ridden away if it was displaying these symptoms. Till tomorrow, fingers crossed.

[Mincehead]

I use NGK iridiums in all my vehicles, even in my five cylinder car, they definately clean up carburation. The car is injected but that too is more responsive with them fitted than with the stock plugs. The stock plugs are similar to the old Lodge type with four outer tangs coming in to meet the centre electrode.
I`m certain your problems are carb related but you just `might` have a plug breaking down, althugh it would tend to display the symptoms across the rev range I would have thought.
Keep us posted.

[dandywarhol]

I don't think Dynojet needles and Factory Pro parts are compatible, I seem to remember folks on Carpe TDM having this problem some years back. FP emulsion tubes and Yamaha needles work well together, FP needles have a different taper profile and are more suited to mid/full throttle use. Look forward to hearing how she runs now...................

Here's how worn tubes look - the FP needle is on the top. Yam tubes are gold colour on the left, wear is the dark area at the top.

On a plus point, I'd say the bikes had an easy life - the pronounced wear that mince mentioned is caused by the engine being running at low revs in a high gear - the wear is caused by the slides rattling back and forward - very common on big Japanese cruisers!

[Kenvis Repesco]

Thanks for that. I have the original Yamaha needles which where taken out when the DJ kit was fitted. If things dont go well I may refit those and see if its better, they are in excellent nick. One thing I noticed is the replacement DJ needles are a different profile to the ones I took out, they are much more like the original Yamaha ones.

[Mincehead]

Time for some fettling and experimentation I think.