Dirty carbs or needing a jet kit?

[MrPresident]

Pulled the carbs on an 01 Vmax project ive been working on (previous owner let it sit for 5-6 years), cleaned em out and replaced parts with fresh carb kits.

Everything is back together and running, she pulls great right up until about 4k. It doesnt die, but the power band drops off noticeably. I did notice the carb boots are pretty dried out, and I have a supertrapp on the stock headers but have a stock airbox. If this does turn out to be a jetting issue I will be switching to pod filters.

Do i need to clean the carbs better? Is there air getting sucked in the intake boot? Or is the stock jetting just going to be wrong because i have slip on exhaust.

Thanks in advance guys

 

[blaxmax]

You can spray wd-40 on the intakes to see if the rpms rise or an unlit propane torch.
Check plugs and white will be to much air from somewhere. Did you check the float levels?
Stock jetting should be fine.

 

[MrPresident]

ill check the boots tonight, and I havent checked floats yet i was waiting to pull them until i figured out if i needed to order a jet kit or not

 

[[email protected]]

Jet kits are not required to run right with a slip on.

Do not buy a stage 1 jet kit, ever!

Stage 7 is good IF you have a full exhaust. Useless with slip ons.

A muscle jet kit is good IF you have a full exhaust. Useless with a slip on.

Do not install cheap pod filters! You will have a bear of a time getting it to run right. If you decide to not take this advice and do it anyways you MUST use air correctors.

Do NOT buy cheap carb rebuild kits. Most notably Keyster. They are known to have poor quality components. Specifically, the brass parts are not machined correctly. Use genuine mikuni parts!

I would check the fuel tank for rust. Very common problem. No reason to do anything until that is fixed. If the tank is bad, you need to clean all lines, pump, replace the filter, and clean the carbs AGAIN.

If the tank is clean I'd make sure all the hard parts are genuine mikuni. Check all O rings, jet block gaskets, coasting enricheners, and slides. Make sure the pilot jets are clear. This is a notorious issue with vmaxes that sit. Set the floats and check the wet level.

As far as carb setup goes, I would order some 150 main jets from Sean Morley. Maybe a set of needle shims too. Put the 150's in. Leave the rest stock. Set AF screws to 2.5 turns out and go from there. Probably won't need the shims but they are cheap and will save you from waiting for them down the road if needed.



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[MrPresident]

Awesome reply thank you. Ill scratch all pods and jet kit ideas.

The tank was actually taken to a shop and fully redone with all the rust taken out and the tank resealed. The carbs had been off the whole time the bike was sitting and did not go back on until after the tank was cleaned. I did redo the carbs and used a K&L supply carb kit from Japan. Is this the garbage kit you were talking about?

Also i cant get Morleys site to work is he still in business? Ive been wanting to order from him for a while now.

 

[[email protected]]

Contact Sean thru email: [email protected]

Keyster is the brand I've heard bad things about. I've not heard good nor bad about K&L.

Definitely check the boots. All of them. Intake to carb, vboost, and carb to airbox. Best to hold in your hand and squeeze. Look for tiny cracks.

Make sure the carbs are clean, clean, clean. Set the floats per the sticky threads in the carb section. Double check the wet level.

You could also have an electrical issue. Check your rectifier/regulator output and the stator. The CDI will cut out if the electrical system is not putting out proper voltage.

 

[blaxmax]

I've used K&L kits and have had no problems with them.

 

[MrPresident]

sprayed starter fluid around the boots, nothing.

damn, I was hoping that was it that would have been easy

 

[caseyjones955]

Maybe someone else already put a jet kit in it, stage one being pretty common. I had a stage one in mine when I bought it and even with full exhaust it fell on it's face at 4k from being stupid rich. Did you happen to notice what jets/needles are in the carbs now?

I have had no luck with Morleys sight either but email him, he is around and has the goods, I just got a jetting kit from him.

 

[blaxmax]

Pulled the carbs on an 01 Vmax project ive been working on (previous owner let it sit for 5-6 years), cleaned em out and replaced parts with fresh carb kits.

Everything is back together and running, she pulls great right up until about 4k. It doesnt die, but the power band drops off noticeably. I did notice the carb boots are pretty dried out, and I have a supertrapp on the stock headers but have a stock airbox. If this does turn out to be a jetting issue I will be switching to pod filters.

Do i need to clean the carbs better? Is there air getting sucked in the intake boot? Or is the stock jetting just going to be wrong because i have slip on exhaust.

Thanks in advance guys

How many plates are in the supertrapp? You want 6-8.

 

[MrPresident]

I THINK i have 6 plates in the exhaust but ill count when i get off work.

 

[MrPresident]

The guy that gave me the bike kept everything but the seat stock so I doubt he threw a jet kit in there. BUT. on the off chance he did what am I looking for? Are they marked differently?

Game plan currently is order the 150 mains and shims from Morley today (email worked great), pull the carbs and deep clean (again) and make extra sure the pilot jets are clear. Set the float level as per the carb instructions in the sticky and go buy a liter of carb cleaner.

Good start?

 

[blaxmax]

Notches in the needle-usually 5.
Also dynajet jets have a "dj" on them and mikunis have a square box with a smaller square box in the inside corner.
When cleaning the carbs be sure to get the 2 jets inside the jetblock.

 

[95spfldmax]

The guy that gave me the bike kept everything but the seat stock so I doubt he threw a jet kit in there. BUT. on the off chance he did what am I looking for? Are they marked differently?

Game plan currently is order the 150 mains and shims from Morley today (email worked great), pull the carbs and deep clean (again) and make extra sure the pilot jets are clear. Set the float level as per the carb instructions in the sticky and go buy a liter of carb cleaner.

Good start?

If you don't have any vacuum leaks then this should resolve your problems. Keep us apprised.

 

[95spfldmax]

Jet kits are not required to run right with a slip on.

Do not buy a stage 1 jet kit, ever!

Stage 7 is good IF you have a full exhaust. Useless with slip ons.

A muscle jet kit is good IF you have a full exhaust. Useless with a slip on.

Do not install cheap pod filters! You will have a bear of a time getting it to run right. If you decide to not take this advice and do it anyways you MUST use air correctors.

Do NOT buy cheap carb rebuild kits. Most notably Keyster. They are known to have poor quality components. Specifically, the brass parts are not machined correctly. Use genuine mikuni parts!

I would check the fuel tank for rust. Very common problem. No reason to do anything until that is fixed. If the tank is bad, you need to clean all lines, pump, replace the filter, and clean the carbs AGAIN.

If the tank is clean I'd make sure all the hard parts are genuine mikuni. Check all O rings, jet block gaskets, coasting enricheners, and slides. Make sure the pilot jets are clear. This is a notorious issue with vmaxes that sit. Set the floats and check the wet level.

As far as carb setup goes, I would order some 150 main jets from Sean Morley. Maybe a set of needle shims too. Put the 150's in. Leave the rest stock. Set AF screws to 2.5 turns out and go from there. Probably won't need the shims but they are cheap and will save you from waiting for them down the road if needed.



Sent from my SM-G900V using Tapatalk

This info is prob already in a sticky but if not one of the moderators should copy and paste it in there somewhere. This is a good overview. Thanks, Mike.

 

[caseyjones955]

http://vmaxforum.net/showthread.php?t=3208

First post here has a pic of all the different needles, wont hurt to make sure you are all stock.

 

[gentsvmax]

2nd that on the carbs being CLEAN, how were they cleaned?