My ride and performance question

dbeller · Jul 18, 2008

Hello all you VMax nuts. I have been around for the past month or so as a recent VMax purchaser. I love this thing (bike and website). A week or so ago I got a great deal on a barely used set of SuperTrapp slip-ons. My '86 is completely stock except for these. The carbs were synced prior to my purchase and it ran GREAT. It still runs awesome, but I have noticed that after accelerating more than about 1/4 throttle, it sounds like the left side exhaust gets much louder than at slow cruising speeds. It's like one of the carbs that goes to the left side opens up only on medium throttle. It may have done this before the exhaust swap, but I probably would not have noticed it since it was so quiet. Do I need to sync the carbs or do a re-jet (which I totally don't want to do)? Any advice. I don't notice any performance loss, but it sure sounds GREAT! It starts perfect every time, idles perfect, etc. I started with 8 plates on each side of the Trapps and went to 5 yesterday. It toned it down a lot and actually seemed to make the issue more tolerable, but still noticeable. Is it just the change in air/fuel mixture?
Thanks.
Derek
http://www.vmaxforum.net/album.php?albumid=52

lankeeyankee · Jul 18, 2008

Hi Derek and welcome to the forum!:clapping:

I dont have slip ons but I am going to give this a stab.
I am assuming you have good hearing both ears. LOL!
Left side is louder. Did you buy these slip ons used? Possibly need to be repacked if its just a sound thing?
Next I would find a road straight, grab your spark plug wrench.
Start from a dead stop and run the bike through 1st and 2nd WOT once you get to top RPM in 2nd pull the clutch in and kill the motor.
Pull the plugs and compare them left to right side. This will tell you if you have a carb problem.
Since the carbs were synched I dont think its a carb issue, unless the person doing them didnt do it properly, meaning I set my carbs in at idle 1250 RPMS once I get them all pretty much even I will increase the throttle to about 5500-6000 and see if they stay equal as the RPMS increase, if they dont than I know its most likely spring pressure and adjust them to where all my slides rise even with each other.
Thats my idea, I am sure more will post with ideas but thats a start.

dbeller · Jul 18, 2008

Thanks Yankee,
I don't think the left side is louder. Actually it is quieter than the right when taking off, but after about 1/4 throttle and up, it sounds like it "kicks in" more and gets as loud as the right side. The pipes had 600 miles on them before I purchased them (so they say). I really don't want to start tinkering with adjustment screws, as I don't want to "screw" anything up. I don't have experience syncing carbs, I have no carb tuning tool, and I don't really want to pay someone big bucks to do it. I wish it would be something simple, but I'm sure it's not. I can definitely live with it, but I don't want to do any damage. I will check the plugs as my first attack. I will also drop in some Seafoam as I have great luck with that in the past. Thanks again.

lankeeyankee · Jul 18, 2008

Derek

Dont be intimidated with synching the carbs man, really its an easy tuning process and there are so many people here that can help! Even if you screw it up someone here has done it also! You seem very good with your writing so I dont see that being a problem.
Search for carb synching here I know there has been many posts on it and what the guys use here. Once you synch your carbs for the first time you will be able to do it in 15 mins afterwards. Its easier to synch carbs than it is to replace spark plugs IMO.
As I think about it sounds almost like one of your diaphrams arent rising quick enough.

dbeller · Jul 18, 2008

After doing a quick search in the Carb/Tuning section, duh, I found the easy step by step instructions. I will have to get my hands on a carb tuner tool. My neighbor works at a bike shop. Maybe he can hook me up. He would probably help me, but I hate to ask him to work on my bike when he does that 5 days a week. Great info!!

lankeeyankee · Jul 18, 2008

I think everyone here uses a CARBTUNE brand. Not sure though. I just use a basic mercury gauge with glass tubes, basic cheapo from JC Whitneys.
The onlything is you have to becareful not to let it drop lower than the carbs when your tuning or it will suck the mercury into the engine, and thats not good!!
More information goto WWW.VMAXOUTLAW and you can download the VMAX service manual there, which is very useful in the learning curve of the VMAX. Best of all the Service Manual is free!:clapping:

Hercules · Jul 18, 2008

Maybe the accelerator pump shot is clogged just a guess!

Shuriken · Jul 18, 2008

OT - what front disc rotors are those on your bike?

dbeller · Jul 18, 2008

XSiveMaximus said:
OT - what front disc rotors are those on your bike?

Maximus,
If you are referring to my rotors, they are Braking brand. I can check and see if there is a number on them if you'd like. They were on it when I bought the bike, both front and rear.
I am getting a low speed squeek/rub from both, but that may be a result of the pads. The rotors are in nice shape, so I bet there are cheap pads on there or some crystallization has occurred.
Derek

4gasem · Jul 18, 2008

Hercules said:
Maybe the accelerator pump shot is clogged just a guess!

LOL No accelerator pump on CV carbs. Just flat slides and old car carbs I think.

Mitchell · Jul 18, 2008

dbeller said:
Thanks Yankee,
I don't think the left side is louder. Actually it is quieter than the right when taking off, but after about 1/4 throttle and up, it sounds like it "kicks in" more and gets as loud as the right side. The pipes had 600 miles on them before I purchased them (so they say). I really don't want to start tinkering with adjustment screws, as I don't want to "screw" anything up. I don't have experience syncing carbs, I have no carb tuning tool, and I don't really want to pay someone big bucks to do it. I wish it would be something simple, but I'm sure it's not. I can definitely live with it, but I don't want to do any damage. I will check the plugs as my first attack. I will also drop in some Seafoam as I have great luck with that in the past. Thanks again.

Bike looks good Derek!

Bring that thing to the Super Magna Meet and I'll synch the carbs for ya.
Just a little info for your set up. I'm running 8 discs on my Trapps, had it dynoed and it was just a little on the rich side. But not enough to hurt anything. I think I have my FA pilots adjusted 3 turns out. Anyway, I pulled a 116.9 rwhp @ 80 ft lbs torque and was pretty happy knowing its running to spec. So since you are running 5 discs per side now, its gotta be running really rich IMO. Add discs to lean and increase sound, remove discs to richen and reduce sound. And for piece of mind........synch those carbs!

dbeller · Jul 18, 2008

Thanks Clay. I will check the mixture. I may put a couple more discs in. I would love to be able to take my old Super to the meet if I still had it. I think my work schedule may prevent me from attending the meet, but if I can get off, I could make the 3 hour trip either with trailer or riding the max. It would be a fun trip. I really miss the conversations taking place on the SuperMagna forum. I guess I could still browse, but it would just make me miss the Super more.
Derek

shawn kloker · Jul 18, 2008

dbeller said:
Hello all you VMax nuts. I have been around for the past month or so as a recent VMax purchaser. I love this thing (bike and website). A week or so ago I got a great deal on a barely used set of SuperTrapp slip-ons. My '86 is completely stock except for these. The carbs were synced prior to my purchase and it ran GREAT. It still runs awesome, but I have noticed that after accelerating more than about 1/4 throttle, it sounds like the left side exhaust gets much louder than at slow cruising speeds. It's like one of the carbs that goes to the left side opens up only on medium throttle. It may have done this before the exhaust swap, but I probably would not have noticed it since it was so quiet. Do I need to sync the carbs or do a re-jet (which I totally don't want to do)? Any advice. I don't notice any performance loss, but it sure sounds GREAT! It starts perfect every time, idles perfect, etc. I started with 8 plates on each side of the Trapps and went to 5 yesterday. It toned it down a lot and actually seemed to make the issue more tolerable, but still noticeable. Is it just the change in air/fuel mixture?
Thanks.
Derek
http://www.vmaxforum.net/album.php?albumid=52

When I had supertrapps,One of them had nothing coming out at idle.The packing blew out of one before the other.With the factory headers and crossover it was allowing all the exhaust to exscape from the blown out trapp.Repacking them cured it.

shawn kloker · Jul 18, 2008

dbeller said:
Thanks Clay. I will check the mixture. I may put a couple more discs in. I would love to be able to take my old Super to the meet if I still had it. I think my work schedule may prevent me from attending the meet, but if I can get off, I could make the 3 hour trip either with trailer or riding the max. It would be a fun trip. I really miss the conversations taking place on the SuperMagna forum. I guess I could still browse, but it would just make me miss the Super more.
Derek

I just saw a beautifull red super magna in my town.Big fat guy on it though with really stupid looking bash bar thing on the front,huge windshield and dorky 3 foot tall sissybar.

robsplatf4 · Jul 18, 2008

Derek,

Where are you at in OK, I may be able to help you out.

dbeller · Jul 18, 2008

I am in Broken Arrow/Tulsa.
It sounds like the packing may be part of the issue. Thanks guys for all the leads.
Robert, let me know where you are and maybe we could meet up sometime.

robsplatf4 · Jul 18, 2008

dbeller said:
I am in Broken Arrow/Tulsa.
It sounds like the packing may be part of the issue. Thanks guys for all the leads.
Robert, let me know where you are and maybe we could meet up sometime.

I'm in the OKC area.

Shuriken · Jul 18, 2008

dbeller said:
Maximus,
If you are referring to my rotors, they are Braking brand. I can check and see if there is a number on them if you'd like. They were on it when I bought the bike, both front and rear.
I am getting a low speed squeek/rub from both, but that may be a result of the pads. The rotors are in nice shape, so I bet there are cheap pads on there or some crystallization has occurred.
Derek

Yeah, I'd be interested in knowing whatever info you have on the rotors, just out of curiosity.

Hercules · Jul 18, 2008

4gasem said:
LOL No accelerator pump on CV carbs. Just flat slides and old car carbs I think.

Shows ya what I know! Ive got flatsides well[vgas] and had this problem!LOL

dbeller · Jul 18, 2008

XSiveMaximus said:
Yeah, I'd be interested in knowing whatever info you have on the rotors, just out of curiosity.

Maximus,
Here are the markings on the rotors, front and back are the same. BRAKING brand. Two codes engraved on them: YA05F1 and KBA61005A. I assume they are stock size since they measure 11" in diameter.
After a quick google search of the 1st code I got this page from a catalog at Chaparral Motorsports. It doesn't have the price, but an 800 number to call.
http://catalogs.google.com/catalogs?id=Xi5HgqDHZ5QC&pg=PT92&lpg=PT92&zoom=4&dq=braking+ya05f1

My ride and performance question

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