COP(Coil On Plug) for Mr. Max!

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ok no problem, thanks. i'll return em and get the proper ones. didnt look at the number, just the description. now a guy knows. let ya know when they come in. In meantime. I got the harness. I can start preparing the harness. It's all together now, need to take tape off etc.

waht lengths should I have the COPS set at? I'll have to make em.. reminding myself here, use COP harness end, cut and solder connection from currently installed coil.. yeah, how long should each be? for cyl. 1,2,3,4. Wodner what length blax makes his at..

Is there a clear removal guide to get rid of old coils? the rear two seem easy. i dont want to leave them in. I will take them out... I think blax supllies his customers with a write-up but i'm not sure. anyways i'll do these things while i wait for proper cops to show up. thanx all.
 
I left the front coils on. It can be a real horror show to get the screws holding them on loose... I figure the weight of the coils will help keep the front wheel down when Zilla hits the boost.. LOL..
 
Just wanted to add a lil update:

So far, i've run across two types of Denso COPs. The type that the Hayabusa/GSXR's use work very well. There is another type that is a little longer and they neck down just before the rubber boot that sits over the plug(The Honda F4 and F4i use thes). These work well, but their length makes it harder to get on the plug. They both use the same electrical connector on the top. They are not a ton trouble, but personally i like the looks/ease of install/removal of the shorter type.
Here are the bikes that use the SHORT COPs(that i've found so-far):
98-2000 GSXR600 SRAD
01-03 GSXR600
98-99 GSXR750 SRAD
00-05 GSXR750
01-08 GSXR1000
99-08 Hayabusa(GSX1300R)
02-08 R1
99-02 R6
04-07 R6
03-08 CBR600rr
03-06 ZX6/ZX636(maybe the 07-up as well, just have not verified that yet)
98-03 ZX9
00-05 ZX12
06-08 ZX14


I found one set of R6 coil sticks that said they were 03 and they were the long type. Not sure if that was a typo or what. So, on the R6 coil sticks, i'm not 100%. Might be good to shy away from the R6 cops anyway due to the previously posted problems with some of them, at least on the 03-04 R6's.
These use the longer type COPs:
CBR929(all years)
CBR954(all years)
CBR f4/f4i
CBR1000rr(04-08)
98-02 ZX6
Looks like the wiring harnesses from ANY of these bikes will work on any of the coil sticks(long or short).

Just wanted to pass the info along. Hope this info is helpful.
 
Hi All,

I'm new to the forum and a 2005 V-MAX. I am having a problem with the left two cylinders not firing right. I tried to sync the carbs but that was a bust.I can get cylinders 1 and 2 to sync and I can get cylinders 3 and 4 to sync but i cannot for the life of me get the right and left sides to sync together. here is a huge difference in the level from the right and left banks on the gauge.

It also sounds like I'm dropping a cylinder on the right side of the bike. Any thoughts would be appreciated. I was thinking of converting to the COPS as well. What would I need for this conversion?
 
I bet your pilot jets (fiche #42) are clogged. Your description strongly-suggests it. It's worth-it, learning how-to clean them, because having a competent shop do them will probably cost you several hundred dollars in labor. You are required to remove the carbs, and to-remove the float bowls, then the jet blocks, to do it. I suggest replacing screws with allen-head cap screws for the diaphragm cap covers for the CV slides, and the float bowls, at a minimum. A well-stocked hardware store should be able to furnish those.

Removing the carb blocks often will result in torn gaskets (fiche #35), so I recommend having those on-hand before the tear-down. You may get lucky, and be able to re-use them, but if you have them on-hand you should be able to remove, to clean, to reassemble, and to re-mount the carbs in a day.

An ultrasonic cleaner is what I find to work best for cleaning, one big-enough to do the assembled carbs together costs $$$. You can use the one Harbor Freight sells, if you split the carbs into two pairs. Take lots of pics to guide yourself in the disassembly/reassembly.

Usually the left front cyl is prone to becoming obstructed because of using the sidestand, and the migration of fine particulate material from a corroded gas tank, or bad gas. Because that's a low-point on the fuel delivery system in the carbs, the crud stops there. Does the 'dropping the cyl.' occur at idle, and off-idle, but not occur at the upper-half of the rev band? The temperature of the exhaust pipe using an infrared temperature gun would reveal a very-different reading on the cyl cutting-out, and would quickly come to temperature once it begins to fire normally, and then drop in temperature as the revs drop.

The pic is a pilot jet with a single strand of stainless steel wire being used to clean an obstruction. Might as-well check the float levels while you're in-there, it makes a difference in fuel economy and smoothness if they're off.

VMax carburetor.png
VMax pilot jet.jpg
VMax FloatLevel bowl off.jpg
 
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I bet your pilot jets (fiche #42) are clogged. Your description strongly-suggests it. It's worth-it, learning how-to clean them, because having a competent shop do them will probably cost you several hundred dollars in labor. You are required to remove the carbs, and to-remove the float bowls, then the jet blocks, to do it. I suggest replacing screws with allen-head cap screws for the diaphragm cap covers for the CV slides, and the float bowls, at a minimum. A well-stocked hardware store should be able to furnish those.

Removing the carb blocks often will result in torn gaskets (fiche #35), so I recommend having those on-hand before the tear-down. You may get lucky, and be able to re-use them, but if you have them on-hand you should be able to remove, to clean, to reassemble, and to re-mount the carbs in a day.

An ultrasonic cleaner is what I find to work best for cleaning, one big-enough to do the assembled carbs together costs $$$. You can use the one Harbor Freight sells, if you split the carbs into two pairs. Take lots of pics to guide yourself in the disassembly/reassembly.

Usually the left front cyl is prone to becoming obstructed because of using the sidestand, and the migration of fine particulate material from a corroded gas tank, or bad gas. Because that's a low-point on the fuel delivery system in the carbs, the crud stops there. Does the 'dropping the cyl.' occur at idle, and off-idle, but not occur at the upper-half of the rev band? The temperature of the exhaust pipe using an infrared temperature gun would reveal a very-different reading on the cyl cutting-out, and would quickly come to temperature once it begins to fire normally, and then drop in temperature as the revs drop.

The pic is a pilot jet with a single strand of stainless steel wire being used to clean an obstruction. Might as-well check the float levels while you're in-there, it makes a difference in fuel economy and smoothness if they're off.

View attachment 71593
View attachment 71591
View attachment 71592
 
Thank you Fire-Medic,

What a great write-up and excellent info!The problem seems to only be at idle. The bike runs really strong everywhere else. I shot the head with an inferred temp gun pointed at the plug next to the spark plugs to see a temperature difference of around 20°f between the right and left sides. 220°f left side verses 200°f right two cylinders. You can lay your hand on the cylinders and feel a temperature difference from the right side verses the left side.

The right and left cylinders are running the same temperature "side to side as a pair" , but not equal from the left two cylinders and the right two cylinders if that makes sense.

I do smell gas at an idle though, and that's why I thought it might be a dead cylinder but the pilot clogged idea sounds realistic to me since I have no idea what the previous owner did to the bike.

The bike has a complete UFO exhaust ,4 into 2 with the 1.5" inserts so I can see that they had to remove the carbs to probably re-jet. It also has a Dyanatech 3000 ignition with two Dyanatech coils for cylinders 1 and 3 but they kept the stock coils for the front cylinders 2 and 4. Would this be a problem?

I will order the K&L gasket rebuild kits and pull the carbs to clean them. I can handle tearing them down, I just have never worked on a V-Max. I do already have the Harbor Freight ultrasonic cleaner so that's taken care of. What do you suggest for a cleaning solvent?
 
In my original post, I said it was the left two cylinders not firing right but I mad a mistake on what side was causing the problem. It was the right side giving me problems. I m very sorry
 
For the ultrasonic cleaner, H2O & a bit of Dawn dishwashing detergent is good, many people use that. You don't need much. The combination of warm water and the detergent gets-into the passageways.

Aim the temperature gun at the exhaust headers, 4 or 5 inches below the cylinder exhaust ports. That's where you're going to-notice a difference of a couple hundred degrees, if one cyl isn't firing, especially at-idle. If your intermittent issue is 'only at-idle,' I can almost guarantee it's a plugged pilot jet or jets.

Are your DYNA coils the green ones? Those are the ones to use, they're the correct resistance for the OEM ignition box to work. Sean Morley can confirm, that the Ignitech is not concerned with primary coil resistance. There shouldn't be any-issue using two stock coils and two DYNA coils.

Many moons ago, when Yamaha's performance two stroke was the R5, RD350 and the later RD400 twin-cylinder, and when points ignition was still being used, an easy hop-up for the two-stroke twins was to put a better-set of ignition coils on the bikes. One of the big magazines had a popular article about swapping a pair of K-Mart automotive coils in-place of the stock OEM coils, to help the ignition system to fire-better, and there were many Yamahas running-around with their aftermarket primary coils strapped-to a frame downtube because of space limitations.
 
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Thank you!

I'll check the temperature at the header as you suggested. The coils just have a blue Dyna label on them and the coils themselves, are black.

I know there is no resistors inline of the Dyna coils. How do I know what resistor to use? I do not see any info on it from Dynatek. I do have the Dynatek 3000 ignition box in the bike thopugh .The previous owner gave me the stock CDI box with the purchas of the bike.

I like the history lesson. I thought latter on that the motor for the RD350 was eventually worked over and put in the Yamaha Banshee 4-wheeler? That was a crazy fast 4-wheeler!

Thanks again for the help
 
okay,

Finally got to rebuilding the carbs on the bike.Used the K&L rebuild kits which are a very good kit by the way.

To my surprise,the carbs were remarkably clean and the only real issues was the crud built up on the bowel sealing surface. Not a big deal since it cleaned up really nice.

What I did notice before I pulled the carbs was that there was a bit of slop in the butterfly action between the right and left sides of the bike.The linkage arm that connects the left and right banks had a decent amount of slop in it. The butterfly's on the left side of the bike would open before the right side.

I suspect this caused the majority of my syncing issues. Since I had to completely split everything to do the rebuild,it was a good time to put a new linkage rod on.

Put it all back together and she synced really nice! thanks for all the help
 
I agree. The factory style connector is very well weatherproofed and has a lock to keep it secrure.
If you get an R1 COP set with the wiring harness, are the large & small wiring plugs 🔌 plug for play? Or do you have to hack them to connect to the old Vmax wiring harness?
 

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