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Carb Mods and Tuneup


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So after having a bad experience with a local shop trying to tune my carbs by ear, I decided I would tackle this myself or hopefully with some fellow VRs. So understand this, I have no mechanical background and am clueless on this.

 

Im leaving to Colorado with my 83 first Gen in August (last week) so will be hitting this quickly. My thought is to try to do all at once. So I was looking for help from here to create a checklist of things to do.

 

1) first on the list is the new TCI from Dingy. After reading many post it seems like this would be a must an because I felt like some of my bikes symptoms are related. Plus it sounds way better than the possible diodes cording in the 30 year old OEM.

 

2) I believe it sounds like it would be wise to replace the "sliders and diahprhams" in the carb. Sounds like I need 4. Is there a current best place to order them from?

 

3). Plug and remove the 4 boxes of the Ycis ports. This one is still hooked up.

 

4) Skydocs's needle shim kit. Question is do I order 4 kits or does 1 kit take care of all the carbs.

 

5) sea foam of coarse.

 

6) I guess new plugs are in order since I have been doing the sea foam. Any recommendations what kind.

 

Long story short, the bike ran good before shop adjusted carbs other than lower mpg. Some of the list is preventative maintaince and if I'm there might as well do it. Any suggestions would be great. I'll be ordering a Carbtune too.

 

Last thing, anyone know someone in the Southwest Missouri (Branson) area that could mentor this process on the day of. I would certainly make it worth while. Or possibly someone wanting a Branson vacation :-).

 

I dont care care about popping wheelies but would like to know of this "power". Mainly wanting better mpg.

 

Good thing is there is no fuel leaks on the garage floor after riding it. I have some pro video and photo equipment and would love to document this process for other noobs like myself. Then I'll be filming my adVENTURE to Colorado too

 

thanks in advanced.

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So after having a bad experience with a local shop trying to tune my carbs by ear, I decided I would tackle this myself or hopefully with some fellow VRs. So understand this, I have no mechanical background and am clueless on this.

 

Join the crowd, but we lean on each other and get threw it.

 

Im leaving to Colorado with my 83 first Gen in August (last week) so will be hitting this quickly. My thought is to try to do all at once. So I was looking for help from here to create a checklist of things to do.

 

1) first on the list is the new TCI from Dingy. After reading many post it seems like this would be a must an because I felt like some of my bikes symptoms are related. Plus it sounds way better than the possible diodes cording in the 30 year old OEM.

 

Do not toss out your old TCI, It is not hard to replace the Diodes and then there is another spare floating around for emergencies.

2) I believe it sounds like it would be wise to replace the "sliders and diahprhams" in the carb. Sounds like I need 4. Is there a current best place to order them from?

 

Unless there is an obvious problem with the sliders they seldom need replacing. The diaphragms when held up to the light if there are any pin holes they need replacing, not a bad job to do.

3). Plug and remove the 4 boxes of the Ycis ports. This one is still hooked up.

 

I am not sure how much if any difference this makes.

4) Skydocs's needle shim kit. Question is do I order 4 kits or does 1 kit take care of all the carbs.

 

Are You sure you need this? The shims will lean out the top end mixture. If your bike is not rich this can over lean it and loose power. One kit does all 4 carbs. Do this while doing the diaphragms.

5) sea foam of coarse.

 

Heavy dose if you are trying to fix an issue. per the can instructions for maintenance.

6) I guess new plugs are in order since I have been doing the sea foam. Any recommendations what kind.

 

Replace plugs after the heavy seafoam, SeaFoam is hard on plugs. No one has found anything better that the stock OEM NGKs.

Long story short, the bike ran good before shop adjusted carbs other than lower mpg. Some of the list is preventative maintaince and if I'm there might as well do it. Any suggestions would be great. I'll be ordering a Carbtune too.

 

Hurry and get the CarbTune on order, it takes about +/- a full month to get here.

Last thing, anyone know someone in the Southwest Missouri (Branson) area that could mentor this process on the day of. I would certainly make it worth while. Or possibly someone wanting a Branson vacation :-).

 

I dont care care about popping wheelies but would like to know of this "power". Mainly wanting better mpg.

 

Good thing is there is no fuel leaks on the garage floor after riding it. I have some pro video and photo equipment and would love to document this process for other noobs like myself. Then I'll be filming my adVENTURE to Colorado too

 

thanks in advanced.

 

Good luck, wish you were closer.

 

We love pics and videos......

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Had the stock NGK DPR8EA-9 plugs. Bike ran OK, but I've been fighting to get it running well. Fixed some of the "roughness" by fixing the high resistance in the OEM spark caps.

 

Then went looking for the Yamaha service bulletin (#M83-030A) recommended plugs - DPR8EV-9 (thin wire gold electrode) or DPR8EX-9 (thin wire platinum electrode). They are an additional recommendation in the Tech bulletin to help eliminate misfires.

 

Gold is no longer made, the platinum I can get but are special order at all my local parts places.

 

Went to NGK DPR8EIX-9 (thin wire iridium electrode, NGK stock #2202) which is the "step up" from the platinum tip.

 

Will never, EVER, go back to DPR8EA-9 again. Sharper spark, runs much better, even pulls cleanly when lugging in high gears between 2000-3000 rpm with the missus on the back.

 

Shop gave me a military discount which made them just about the same price as the regular old DPR9EA-9.

 

Well worth the swap.

 

:)

Edited by Great White
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All of the things you have outlined to get done are things which should eventually be done on a bike of this age....I'm just not sure they all "need" to be done immediately in order to fix your issue...

One thing that is often overlooked is properly setting your valve clearance....your carbs cannot be properly sync'd/set without your valve clearances being within spec....if you look to the very beginning of the FSM under "Carburetor Synchronization" the very first Note reads - "Valve clearance must be set properly before synchronizing the carburetors." The engineers at Yamaha went to great lengths to make sure this is the very first thing you read before you attempt to do a sync. Unfortunately many are intimidated by this process and choose to ignore it. Your carb sync/set will be infinitely easier and last much longer if your valves are set first.

I can see you've already invested a considerable amount of both time and money, but failure to properly set your valves before your carb sync could lead to the same issues popping up again.

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Patmac is correct, if one of the intake valves is out of tolerance it will suck either more or less air depending on which way it is out of adjustment. This of course is going to affect the air flow through the carb, affecting the vacuum level of the carb...

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While having the valves in proper adjustment is needed for a perfect carb sync. Checking the valves every time you sync the carbs is not necessary or realistic. How many miles are on your bike? Mileage is what determines when the valves need to be checked.

 

Valve adjustment just sounds scary. If you can take apart a carb you can do the valves. Even I did my valves. It is not hard, just takes a lot of time. and it will be a great satisfaction when you are done.

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If the valves have never been done then they are due. Recommended is every 26K.

If they have been done before then you are probably OK for a while yet.

 

One way to get a clue on if they have been done is to look at the edges of the valve cover gaskets. There is a half circle part on the side of each head. if that has cracking or you have oil leaks from the valve covers, then it is very old rubber and the valves likely have not been done before. If the rubber looks fairly fresh, they may have been done. This is not a guaranty either way, just another clue.

Edited by Flyinfool
Fixed fat finger
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