Bike revs up and down

[calvinTZR2503xv]

Ok thanks peterbike, this seems more like my problem...so what part of the electrics are responsible for the bikes peformance, do you think it has something to  do with the powervalves or the cdi....

[calvinTZR2503xv]

Hi there, an update on the situation:

The bikes problem has been identified 100% at electrical, powervalves sometimes work, the indicators sometimes work, then don’t. Could all this be caused by a bad earth?

[ash33]

Yes but being electrical it makes it hard to find.

I would start with the charge circut by putting a multi-meter over the battery while the bike is running. If the volts are going up and down (or are below 14 Volts which usually indicates a faulty battery) as the bikes rev's rise and fall then you have and issue with the charge circut. Start at the battery and work your way along the loom.

One of the most common issues with bad Neutral wires is broken battery neutral wire.

[calvinTZR2503xv]

Thanks Ash, yeah u have been really helpful. I am basically starting at the battery and re doing all the bad wires and joints. A lengthy time consuming task but it will be a process of elimination with success at the end. When it rains it pours as it seems now  have yet another problem, my bike whilst idling, petrol running out of bottom of carbs out of the overflow outlet, when I stop the bike it stops, both carbs are doing this now, I don’t have a fuel filter between my tank and the carbs, my bike was standing for 8 months before that, do you think the carbs are blocked with rust/dirt...thanks please feel free to affer your advice

[ash33]

In my experience with carb over flowing, albeit on other brands of bike, the 2 main causes are float height or float valve O ring.

At a guess it sounds like your carb floats are vibrating and letting fuel leak through the needle and seat, I'd suggest re-checking your float heights and possibly reducing the float height a fraction. If re setting your float height doesn't work it has to be the O ring is faulty/perrished.

Ifthe float has exessive movement you can hold the revs at 3000-5000 rpm the vibration will smooth out and the floats may not move as much, if this is the case the over flow should stop.

[calvinTZR2503xv]

Thanks a lot Ash, that really helped with the carbs. No more leaking, it was just idling very rough making the carbs leak, but when idling up it stopped. Just one more thing that I need to sort out, the bike has this electrical problem where the powervalves stop working, playing with the wire loom or going over a bump then they start to work again. ...my big question is..what part of the electricals are responsible for the powervalves to be open and closed?? Where do I start to look for this bad earth or bad connection...please somebody can point me in the right direction...thanks a lot guys

[Warwick]

Start with the PV servo wiring itself - and the connection to the main loom (connector should be in the little junction box under the tank). If there's nothing obviously amiss then I'd suggest you take it to an auto electrician to be honest - unless you are happy to (potentially) work through the full loom looking for problems. An auto electrician should be able to trace the fault much quicker Id think.

[calvinTZR2503xv]

great thanks a lot will do that....keep you posted....almost there

[calvinTZR2503xv]

Hi there, thanks to everyone who has replied to this thread over the weeks/months, my bike finally running better, managed to sort out the electrical issues, it was a weird ghost in the wiring but by changing out the entire loom this has been fixed. Now the issue of the bike running to rich, took out plugs and they were black and sticky and wet, exhausts pipes are dripping oil, opened the carbs to discover the main jets were 270, i am sure this is too much, shouldnt they be at 185 or 200, please can someone confirm what the main jets should be for 3xv standard carbs....please reply to this asap...thanks guys

[Marty stinkwheels]

Std 91 R 3XV top carb 190 lower carb 260
later R top carb 200 lower 270

I think thats right
Hope this helps
Martin

[calvinTZR2503xv]

yeah great thanks..

[wullie3XV9]

..... Now the issue of the bike running to rich, took out plugs and they were black and sticky and wet, exhausts pipes are dripping oil, opened the carbs to discover the main jets were 270, i am sure this is too much, shouldnt they be at 185 or 200, please can someone confirm what the main jets should be for 3xv standard carbs....please reply to this asap...thanks guys.

Sounds like your 2T oil pump's not set up correctly & pumping too much oil in.
Is there still a fair amount of blue smoke coming out the exhausts, when moving, once the engine's hot?
Mine was exactly the same when it was first delivered to me & it was because the pump was set up wrongly.
( Too much 2T oil going into the engine ).
It was laying a blue smoke screen when on the move, which was visible when looking in the mirrors !
There was also excess oil dribbling out of the tail pipes.

Once I'd checked & adjusted the pump in accordance with the 3XV1 workshop manual, ( & synchronised the carbs & the oil pump settings ), it's been fine ever since, with any smoke only visible when the engine's idling.
The inside of my exhausts tailpipes are now usually fairly dry with dark brown / black deposits, only getting slightly wet with oil after prolonged slow speed riding.

For your information, the stock main jets for my '93 R / RS 28 mm carbs are 190 left, 270 right.

                                    Hope the above helps.  

P.S.  Just a thought, your engine hasn't started using gearbox oil, has it ?

[calvinTZR2503xv]

Hi Wullie thanks, so the oil pump that makes sense, so that is situated on the right side by the bottom air filter? Also when you say left and right you mean top and bottom? 190 top and 270 bottom. Many people have confirmed this now, my question to you is why the difference in jet size where a KT1 will have the same size jets...just curious as to why this is the the case with 3xv...please can someone get me the answer for this as soon as possible, very curious. Thanks a lot to all

[wullie3XV9]

Hi Wullie thanks, so the oil pump that makes sense, so that is situated on the right side by the bottom air filter?  Also when you say left and right, you mean top and bottom? 190 top and 270 bottom. Many people have confirmed this now, my question to you is why the difference in jet size where a KT1 will have the same size jets...just curious as to why this is the the case with 3xv.....

Yes, Calvin. 2T oil pump below / behind bottom / R/H airbox. Unfortunatly, the bottom airbox has to be removed to allow access to adjust the pump, which means removing the fuel tank to remove the vertical intake stack before removing the bottom airbox ! ?   
Mind you, if you go to the trouble of synchronising both carbs & the 2T oil pump, the fuel tank & BOTH airboxes & intake stacks have to come off anyway. BUT, it is worth all the aggravation, as you'll have a sweeter running engine as a result.

Yes, when I say left & right I mean upper ( left ) & lower ( right ). Force of habbit after owning several parallel twin strokers over the years.

Your different sized main jets in 3XV carbs queery is probably a result of the different volumes & intake lengths of each airbox. Parallel twin carbs ( & some V twins come to think of it ) share the same airbox & have the same intake lengths, if you know what I mean.  I've cut away the restrictive tapered intake on my upper airbox lid, which has resulted in the upper ( left ) carb having to be jetted up from a 190 main jet to a 220, ( tried a 230 first ), & have also gone down to a 260 main jet on the lower ( right ) carb as a result of "plug chop" runs, ( after fitting the set of exhausts Martin77 made for me ). As a result, both main jets are "closer" together size wise.
I'm certain Martin77 told me stock 3XV exhausts each have a different "tuned" length, which also may have a bearing on main jet size too.

                                             Again, hope the above helps.    

[calvinTZR2503xv]

yeah man thanks a lot....that really helpful, makes perfect sense...just the only thing now i hope the guy that works on my bike knows about how to adjust the oil pump and synchronize the carbs. Will post updates thanks