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Another carb question...

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Old 08-07-2012, 05:57 PM
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Another carb question...

So, after riding around a bit today my bike decided it didn't want to run well at the 5K and above RPM range. It bogs down anytime I try to open the throttle, but is fairly smooth if I am easy up until about 5K and then the bike wants no part of it. In neutral it revs
Normally.

After changing the plugs and making sure the air filter is clean, I am inclined to think its in the carbs. Which is well enough.

Earlier in the day, before any symptoms and the bike was running well, the speedo died, and only the speedo, for about a minute before coming back to life. The speedo and other gauges have worked fine for the rest of the day.

My question; Before I take the carbs off, is there any chance there could be some electrical problem I am missing?
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Old 08-07-2012, 05:59 PM
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Sounds as if your R/R may be on the way out.
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Old 08-08-2012, 11:45 AM
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Did you take the tank off? If so it's PVLIR
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Old 08-08-2012, 05:43 PM
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All hoses are/were correct. I was wandering if the speedo blip might have been related to the drivability problems. Everything checked out electrical wise.

Got the tank and box off today. I'm getting into the carbs tomorrow, thanks to silly in-law commitments, and I can't finish her today.

Anything else I might want to pay attention to while I'm in there, please let me know.

Gregg
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Old 08-08-2012, 05:52 PM
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R/RRRRRRRRRRRRRRRRR!
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Old 08-09-2012, 12:34 AM
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Regulator / Rectifier near seat under rear cowl. They over heat and fail. Change for another one, CBR125 model is on mine - twice as big as the VTR one and has fins all over it.
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Old 08-09-2012, 02:23 PM
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I will change the R/R because I am aware of the failure possibility/guarantee. Though I do not believe that it's causing my problem.

This is my first go 'round with SH carbs. Is it necessary to drain the coolant or can I Tee them together or pinch them closed while I work?

Also, from what I've read there isn't much of a fuel filter on the hawk; has anyone tried adding a universal inline filter and if so thoughts or comments?
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Old 08-09-2012, 02:33 PM
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Originally Posted by alternative_vtr
CBR125 model is on mine - twice as big as the VTR one and has fins all over it.
Still shunt based though. May as well go MOSFET if you're getting a new one.
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Old 08-09-2012, 02:54 PM
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Check your electrical grounds for any loose or caroded connections. A bad ground will give you all sorts of wired gremlins. It's kind of doubtful it's something in the carbs unless you got a bit of debris in there that is plugging up a jet or something. But you never know. While you're in them take the time to go through the carb set up thread and set them up accordingly.
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Old 08-10-2012, 11:23 AM
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If the hoses are on corcectly then it sounds like a R\R or a ground issue to me.
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Old 08-10-2012, 11:27 AM
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Originally Posted by ElBandito
I will change the R/R because I am aware of the failure possibility/guarantee. Though I do not believe that it's causing my problem.

This is my first go 'round with SH carbs. Is it necessary to drain the coolant or can I Tee them together or pinch them closed while I work?

Also, from what I've read there isn't much of a fuel filter on the hawk; has anyone tried adding a universal inline filter and if so thoughts or comments?
No need to drain the coolant and if the bike is cold the lines should be fairly empty, so no need to plug them either.

Even hot you will not loose much, so no worries there.

The fuel filters can and often do cause issues.

It is a gravity feed system and the common issue is fuel starvation at high RPM.

I have always just run the stock screen filter and have never had an issue.
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Old 08-19-2012, 01:23 PM
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Well, after going through the carbs and setting them up as the "carb setup" thread suggests the bike ran beautifully. Better than before. For about a week.

Today, I got a bit spirited on the road and the bike was pulling hard and strong. But at about 120 mph, she had enough. I started getting all the symptoms that I thought I had corrected; feels like I'm losing a cylinder at above 5K rpms in any gear. Revs fine in neutral.

I am mechanically inclined, but electrical isn't my thing. It seems that it's electrical at this point. So, what should I check before I take it to the shop? I have very basic electrical skills, and after reading the manual, an ignition system check is beyond my capabilities.

Help is welcome and greatly appreciated.

Thanks,
Gregg
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