TCI Computer

[BrianK]

Just an update on my 1995 Vmax:

I have had it in the shop for a couple months after trying everyones's suggestions and trying everything I could myself.

Mechanic noticed when he came to pickup the bike the left front exhaust pipe was warm while the other exhaust pipes were hot. Showed that the left front cylinder was not firing properly if at all.

Carbs's have been thoughly cleaned 5 times now (twice myself) - My mechanic cleaned them ultrasonically and completely disassembled and reassembled. Carbs are basically new too (came off a 2005 vmax when new and bike was used for the track and carbs drained and stored) All parts in carbs look clean and like new. He Synced multiple times and everytime they were dead on. A/F mixture checked and adjusted and spark is strong on all cylinders. He cleaned the carbs a couple times before the front cyclinder fired properly - must have been something stuck in one of the passageways.


Bike now does not have the high idle problem anymore and all exhausts feel hot to the touch. So it seems to be firing properly now.

But it still has the pop only out of the left rear cyclinder. Bike takes a few minutes to warm up and run without choke. Guess this is normal on most vmaxs. Took it out for a spin but still seems to run a little rough with the pop but alot better than before. Only notice the pop at lower speeds in 1st & 2nd. Seems to accelerate pretty good.

Again this problem started last September. It ran fine before and all of a sudden developed the problem of the popping sound, random high idle and running like crap (probably because of firing on 3 cyclinders). Well at least its running on all cylinders now & idle seems normal after warmup. When putting my hand over the exhaust you can feel the difference of air flow when it pops. Don't know what else to try for the popping issue. :bang head:

I had similar issues with my 85' Vmax and I was getting real tired of "shot gun" cleaning my carbs".

I tried Sea foam, which seemed to help a bit, but it had to be added to every tank full. It also has no cleaning or residual features about it so I looked further.

On 2008 I read about BG Products fuel additive in the Vboost mag. and was impressed with the articles info. about this fuel additive, so I decided to give it a try. The article mentions BG #201 Super charge (small pink bottle) it needed to be added every tank full, but I found out that BG's #203 was the same product, just formulated to be stronger, so it only needs to be added every 3500 miles or so.

I've been using BG Fuel Additive #203 for well over a 1 1/2 years now without any complaints from me or the Max. Not once have I had to deal with fuel related issues.

If you can't find BG Fuel Additives at at your local cycle shop, you can buy direct. I called there Houston branch office to place an order and only paid about $7.00 per bottle for the BG #203. Dealers want about $20.00 per bottle.

Remember, one 11oz. bottle lasts about one year.

I hope that help.

BrianK-5125
Houston
85' Vmax
2000' Vmax

 

[GREEN light BLITZ]

-Clean your air filter,its an easy "check mark" on the list of stuff you already tried but anything(or typically combination of things) can be the answer.

-Make sure you have a good tight seal on your vacuum advance hose that runs from the front left (#1?) cylinder to the advance unit,check it for ANY cracks or nasty spots...if youre not sure about it replace it! This little hose DAMN near made me sell my Max backin the beggining because alll the problems it caused.

-Take a glass jar and clean it out very well, then drain your flaot bowls into it through the drain hoses and look for any particles,even through your carbs have been cleaned and clean and cleaned you would not BELIEVE how much crap can fill your carbs if your tank has rust or dirt in it.(Dont trust just looking into the tank for "stuff" because you wont find any)

-Changing the plugs cant hurt assuming you havent already.Everyone has cleaned plugs before but it might just be time to buy new ones.

If youre gettin good spark its ganna be a fueling issue and at least you know where to look. Just a couple ideas from a fresh set of eyes.

 

[vince95]

Latest update. I have tried everyone's suggestions here and appreciate all the help.

Last Sunday I took my carbs apart again for the fifth time and replaced all the pilot jets with 40's. Everything looks like new inside. This time I did find the smallest bit of varnish in one of the jet block openings next to the main bleed pipe opening. (carb #3) Also a couple floats were a bit off so I adjusted them properly. After reassembling the carbs and trying them out it still ran the same. It takes 10 minutes of running with 1/4 choke before I can take the choke off without dying. Still had popping sound from exhaust and a noticeable miss. Altough there is no more smoke from the exhausts. :bang head:

Then I thought lets try the shotgun again for maybe the 4th time - lost count. I carefully did one carb at a time and probably used almost a half a can of carb cleaner and a lots of compressed air. Also recleaned air filter, checked all fittings for tightness. Just to let everyone know I have installed new carb joints and all new vacuum lines. Also put 3 new rubber sync caps and tighter fitting clamps over them.

This time I started the engine and wow :clapping: no popping. Only ran choke at 1/4 for 2 minutes & took it off and stayed at 1100 rpm and ran smooth. Throttle response was right on with no lag. I took it for a spin and it ran 90% better. Think I finally got it fixed. :eusa_dance:

 

[vince95]

Well thought I had it fixed. I have done the peashooter and shotgun process 6 times now. Once I do the procedures bike runs fine for about 3-4 short rides. Then it starts up popping and runnning rough and then finally it won't run with choke off even after warming up for 10 minutes. Either some small particles are breaking loose in the carbs or small particles are coming from the tank. Inside the tank looks fine with the slightest hint of rust against the walls of the tank. I have tried two new fuel filters (glass type with paper element). Fuel thru the filter looks good and I see nothing building up at the filter. Wouldn't think any particles could get by that would affect the carbs. And if it was due to the tank wouldn't you see some buildup at the filter if it was really bad? :ummm:

Guess next thing to try is to totally disassemble the carbs wihich look like new inside and get them ultrasonically cleaned. Will have to find someone or somehere to take them too. Then replace all the jets. I have replaced my pilot jets and did find on the jet block some hardened residue in one of the jet block openings next to the main bleed pipe that looked like a thin layer of varnish. Maybe still some really small bits of varnish working there way into the pilot circuit. These carbs were supposedly brand new from a 2005. Bike was bought new and used for the track. The carbs were taken off drained and passages blown out and sat for a couple years.

If that still doesn't work I'm buying a new gas tank and fuel lines. May sound extreme but I am get too frustrated with the situation which has been going on since last Sept. :bang head: I just want to ride.

 

[naughtyG]

If/when you do take them apart, make sure to check out all the rubber parts carefully. Of course all eight diaphragms, but also seals and o-rings, especially around the jet block.

 

[RagingMain]

Well thought I had it fixed. I have done the peashooter and shotgun process 6 times now. Once I do the procedures bike runs fine for about 3-4 short rides. Then it starts up popping and runnning rough and then finally it won't run with choke off even after warming up for 10 minutes. Either some small particles are breaking loose in the carbs or small particles are coming from the tank. Inside the tank looks fine with the slightest hint of rust against the walls of the tank. I have tried two new fuel filters (glass type with paper element). Fuel thru the filter looks good and I see nothing building up at the filter. Wouldn't think any particles could get by that would affect the carbs. And if it was due to the tank wouldn't you see some buildup at the filter if it was really bad? :ummm:

Guess next thing to try is to totally disassemble the carbs wihich look like new inside and get them ultrasonically cleaned. Will have to find someone or somehere to take them too. Then replace all the jets. I have replaced my pilot jets and did find on the jet block some hardened residue in one of the jet block openings next to the main bleed pipe that looked like a thin layer of varnish. Maybe still some really small bits of varnish working there way into the pilot circuit. These carbs were supposedly brand new from a 2005. Bike was bought new and used for the track. The carbs were taken off drained and passages blown out and sat for a couple years.

If that still doesn't work I'm buying a new gas tank and fuel lines. May sound extreme but I am get too frustrated with the situation which has been going on since last Sept. :bang head: I just want to ride.

You can send them to me
See my post
http://www.vmaxforum.net/showthread.php?t=10537
The charity this time around is Deaf Kids Kamp. It is the Poker Run I just organizied for DKK.
Cheers

 

[Buster Hymen]

Well thought I had it fixed. I have done the peashooter and shotgun process 6 times now. Once I do the procedures bike runs fine for about 3-4 short rides. Then it starts up popping and runnning rough and then finally it won't run with choke off even after warming up for 10 minutes. Either some small particles are breaking loose in the carbs or small particles are coming from the tank. Inside the tank looks fine with the slightest hint of rust against the walls of the tank. I have tried two new fuel filters (glass type with paper element). Fuel thru the filter looks good and I see nothing building up at the filter. Wouldn't think any particles could get by that would affect the carbs. And if it was due to the tank wouldn't you see some buildup at the filter if it was really bad? :ummm:

Guess next thing to try is to totally disassemble the carbs wihich look like new inside and get them ultrasonically cleaned. Will have to find someone or somehere to take them too. Then replace all the jets. I have replaced my pilot jets and did find on the jet block some hardened residue in one of the jet block openings next to the main bleed pipe that looked like a thin layer of varnish. Maybe still some really small bits of varnish working there way into the pilot circuit. These carbs were supposedly brand new from a 2005. Bike was bought new and used for the track. The carbs were taken off drained and passages blown out and sat for a couple years.

If that still doesn't work I'm buying a new gas tank and fuel lines. May sound extreme but I am get too frustrated with the situation which has been going on since last Sept. :bang head: I just want to ride.

I haven't followed this thread, but how is the charging system? A marginally charged or low charged battery will cause the VMax to run shitty.

 

[vince95]

Everything in the charging system seems to be good. Newer battery and a couple new coils and wires. Have checked all the resistances including the pickup coil and all within tolerance. As soon as I do the shotgun and peashooter it runs like a new bike but symptoms reappear a week later. I think I am going to make a donation to RagingMain and have him clean the carbs and see how that go's. I appreciate all the help and am learning alot about the Vmax.

 

[vince95]

Well, had Fargo ultrasonically clean my carbs and he did an awesome job! Runs smoother at idle. Still has the popping after a few minutes of warmup out of #3 cyclinder (loud pop). Totally went thru the carbs and fuel system, new filter and resealed tank. Newer battery, plugs, coils, wires and tightened all connections and sync is right on. WTF? I am out of ideas. All resistances are right on for the charging system. All carbs 3 turns out, tried 3.5 on #3 and still the pop. Also will pop at all speeds. Can even here it on the highway. Cylinders have all 175 compression. :ummm: :bang head: :ummm:

 

[vince95]

Well I have had enough of this anyone want to buy a 95 Vmax has only 12k miles but cant get it to run without a pop on no. 3 cylinder. Compression good all cylinders at 175. Carbs ultrasonically cleaned 3 times last time by Fargo, new plugs, wires, coil. Have sealed all airbox connections, new exhaust gaskets. Carbs synced multiple times. I must be missing something in trying to tune it up. Have found no leaks around carbs all new rubbers. Shotgun and peashooter a dozen or more times. I have over 7k invested in the bike. Don't know what to do at this point. Really love the bike.

 

[RagingMain]

I know we talked about it and decided against it but maybe we should up your pilots.
I have some 42.5s sitting around and I can send them out.

 

[vince95]

Out of the blue I decided it can't hurt, lets try the shotgun again for the 20th time even though you have my carbs in tip top condition. I completed it and noticed that the airbox rubber (which is new) on cylinder no. 3 had a crease to it. I bet you that every time I seated it, it was probably not completely seated all the way down on the carb. That would explain the popping (sucking more air) and the bike dying when I hit the throttle. Also noticed that one of pilot screws (cylinder no. 1) had the aluminum washer first then the rubber gasket, then spring and the screw. The rest were fine. After correcting these 2 problems I was able to start the bike and take the choke off, set the idle to 1100 rpm and synced the carbs. Right now seems to be running ok. I will let it cool down and try starting again later. I'm hoping I finally got the problems solved. Got my fingers crossed.

 

[PATMAX]

Man I hope you got it Vince. I was hoping that during this ordeal, someone would have ponied up an offer of loaning you a known "good" rack of carbs and elminated the entire carb factor in or out of the equation. If I had a set, I would have sent them along. I know Sean sends out TCIs in the past so you could have eliminated that easy enough. I and many of us had hairpulling issues with our Beloved Maxes. Luckily we have this resource and these guys seem to never give up. The upside is we learn our bikes much more intimately than just shipping them off to the stealerships. You should being noted for your dedication and persistence.

 

[Saml01]

Any updates about this.

My bike has a misfire on the left front (number 2) carb as well, also evidenced that the pipe off this cyl is not as hot as the rest.

Can a post 90 digital TCI computer be swapped into a pre 90 bike? Something tells me no

 

[MaxMidnight]

No, the earlier had two pick-up colis and the later just one.

You would need to fit the later stator and flywheel plus modify the wiring if you wanted to do this.

 

[vince95]

Update

Still runs like shit! Pilot circuit keeps getting plugged up. I do the shotgun and runs good for a ride or two then won't idle properly and will evently die at idle without choke. Tried other sets of carbs, does the same. So I decided to replace with a new gas tank, new hose from tank to fuel pump, new hose from pump to carb. Has all new rubbers at carb base. Disassembled fuel pump and cleaned. New fuel, decided to try different gas - chevron. All this and still can figure it out. I think I have changed every part on the bike. Not to mention $1,500 plus in parts/labor. WTF?????????????????????????????????????????????????????????????????????????????????????????

 

[satariel666]

How about the pickup coil? The PC wire like to rust on the crimps.