A Newbies Adventures in Maintenanceland!

Nice video man! LOL! :laugh:

Sounds like it's hard to start... and needs a good vacuum sync. You'll get it worked out.

...and your neighbors are ging to be less friendly! She's damn loud!

Have fun!

Let er rip for a few days, then check plugs.

If they're really black, make sure you have adjusted your mixture screws properly.

Remember, it should idle around 1000rpm as per an outboard tach, then it will have much better throttle response. The old tachs are unreliable down low, and generally smooth 1000 is like 12-1300 on the old guys.

Enjoy!

thanks, I am going to get the carbs synched soon, I want to take it out for a little 50 km or so tour just to get the motor nice and warm and then change out the oil and filter and re-torque everything. I have to wait for the snow to stop though, it will be a high of 4 degrees tomorrow...so I will have to wait. At least I know it runs, and it feels really nice and snappy with the new cams.

Nice job man!

I pretty much read this entire thread a few pages at a time over the last few days. Really good stuff. I hope to give my bike a complete overhaul like that at some point in the next year or so, I'm sure it needs it... (also a newbie). Great job though, bike looks good, and it looks like all that hard work is going to pay off nicely :woohoo:

Thanks man!

The whole point of this thread was to inspire other noobs. Like I was saying in an other thread today, before this winter the only mechanical work I ever did was changing brake pads, oil, and cleaning the carburetor on my 2 horse johnson (outboard ) I never saw a valve, piston, rings, any of that before in my life, and with my meager arsenal of tools I managed to basically do a top end freshening up, and general bike maintenance overhaul. You can do it, and I hope that me asking the questions gets them out of the way for you.

I tried to go for a ride tonight, and I think I have a vacuum leak, you tell me:

I started the bike up, and rode it to the gas station to get some gas, as I approached the gas station I noticed the idle was hanging at around 3000 and would not drop. I fueled up, started it up and the revs immediately jumped to 4000, so I brake/clutched it down the main road to the neighborhood where I killed it and walked it home.

The other day when I started it up for the first time I didn't go very far, but even with my brief ride I noticed the revs were slow to go back to idle, this time I managed to get the engine nice and warm and the hanging idle just got worse with time. I thought I would try to find the leak, but starting it up in the garage just made it race, so I immediately killed it and thought I would wait for another day when I can test for leaks when the motor is not warm/racing.

First off, is this an air leak somewhere? Would spraying brake cleaner or something like that at the carb boots and holders find it? Thanks boys, I'll get er done yet!

Sounds like an air leak... but could also be the mixture screws too far lean.
Have you tuned the mixture screws yet?

Pull the choke out a little when this happens. If the bike still runs like carp, its an air leak. If it suddenly runs fairly smooth again, its PROBLY mixture.

It's a PITA how the smallest hairline opening somewhere can cause this. The whole system from the airbox snorkel to the exhaust tip, must be perfectly airtight. That means all the carb boot connections on both sides. SUPER air tight. PITA.

Always pays to use a gas resistant RTV like Permatex #2 sealent on the engine boots...

OH yeah. If you have all the air screws at the same defaulted setting, try this:
Get the bike nice fairly hot - off choke and ride for 10 min or so... stop/off, then setup so you can easily adjust mixture screws. Restart bike. Rev the bike quickly to past 4Krpms then release and whatch the tach return to idle.

If it falls very slowly or stays just above idle for a sec, its too lean. Turn your BS34 screws counter clockwise a 1/4 turn. If it drops down below the idle, then comes back up to regular idle, its too rich. Turn the screws clockwise a 1/4 turn.
Your trying to fine tune the spot where it returns quickly to idle, but without dropping below, after revving.

Good Luck Man!

I have not messed with the screws at all, just kept em as they were, I figured if I left things as they were I could run the bike for a while and worry about carb tuning when I put the pods on later this summer. I would try to mess with the screws, but when the motor is warm I don't want to start it, with the push of the started button it flies up to 5000 rpm, I have new rings and shit in there so I don't want to mess it up. I think I may be a bit lean since I went from stock exhaust to an open 4-1, this is why I didn't mention it after the 1st ride. You can even see near the end of my video in the other post how I blip the throttle before I put my helmet on how it sort of slowly goes back to idle. It does that for a little bit and then when it is warm it is unridable. I have new carb boots (airbox to carb) and the carb holders didn't seem to have cracks. Is there a heat resistance sealant I could use to seal the interface between the carb holders and the head? That way I could eliminate that as a leak. I was going to get the dynajet kit from Z1 and put the pods on later on, but if I have to take the carbs off again I am not putting that PITA airbox in again! Before this winter the old carb boots were so bad that none of them were sealing and there were leaks all around them, and I didn't have this issue at all, I thought these idles that don't come down at all are from the connection b/n carb and head leaking. If there was one cylinder that was leaking would it cause the whole motor to rev?

Thanks

btw: at the gas station I tried turning that adjustment knob on the back of the BS34s to lower the idle, it did nothing, and now it is all out of whack, is clockwise up or down? Also, when the bike was reving like crazy I tried pulling on the choke and it just revved it up more, I thought maybe it might knock it back down, but it made it rev more.



TeK9iNe wrote:

Sounds like an air leak... but could also be the mixture screws too far lean.
Have you tuned the mixture screws yet?

Pull the choke out a little when this happens. If the bike still runs like carp, its an air leak. If it suddenly runs fairly smooth again, its PROBLY mixture.

It's a PITA how the smallest hairline opening somewhere can cause this. The whole system from the airbox snorkel to the exhaust tip, must be perfectly airtight. That means all the carb boot connections on both sides. SUPER air tight. PITA.

Always pays to use a gas resistant RTV like Permatex #2 sealent on the engine boots...

OH yeah. If you have all the air screws at the same defaulted setting, try this:
Get the bike nice fairly hot - off choke and ride for 10 min or so... stop/off, then setup so you can easily adjust mixture screws. Restart bike. Rev the bike quickly to past 4Krpms then release and whatch the tach return to idle.

If it falls very slowly or stays just above idle for a sec, its too lean. Turn your BS34 screws counter clockwise a 1/4 turn. If it drops down below the idle, then comes back up to regular idle, its too rich. Turn the screws clockwise a 1/4 turn.
Your trying to fine tune the spot where it returns quickly to idle, but without dropping below, after revving.

Good Luck Man!

9am53 wrote:

1. I have not messed with the screws at all...

2. I think I may be a bit lean since I went from stock exhaust to an open 4-1...

3. Is there a heat resistance sealant I could use to seal the interface between the carb holders and the head?

4. I thought these idles that don't come down at all are from the connection b/n carb and head leaking.

5. If there was one cylinder that was leaking would it cause the whole motor to rev?

6. adjusted knob on the back of the BS34s to lower the idle, it did nothing, and now it is all out of whack, is clockwise up or down?

7. Also, when the bike was reving like crazy I tried pulling on the choke and it just revved it up more, I thought maybe it might knock it back down, but it made it rev more.

OK...

1. Start messing with the screws. :laugh: With a 4-1 open pipe, I actually had to change pilots. (But mines huge). Start by lightly seating the screws, then back them out 2 turns for now, cause you don't want to $@#& around w/airbox, thats cool, and this should help.

2. YEP.

3.
Permatex® Form-A-Gasket® No. 2 Sealant

Slow-drying, non-hardening sealant designed for sealing cut gaskets and stamped parts. Allows for easy disassembly if required. Temperature range -65°F to 400°F (-54°C to 204°C); resists common shop fluids and fuels. Use where sealing is more important than adhesion.

Suggested Applications: Valve cover gaskets, oil pan gaskets. etc.

4. The air leak can be anywhere in the intake track, and cause strange undesirable result. For instance: I had a leak at the airbox boot and it caused popping on decel, and the idle to hang slightly when dropping the throttle...

5. YEP.

6. Idle control: Clockwise is raise idle, counterclock - lower idle.

7. It did this because it is relatively lean, and the choke supplied the required fuel to bring the cylinders up to a greater combustion potential.

Make sure to also check that the throttle components (ALL of them) are nowhere near anything that they could get hung up on. Like say a bit of hose clamp pushing up the throttle lifts on the front of carb... check all.


You did do a bench sync at least right?
To set the idle: Unscrew the idle control know until you can visually see the throttle lifts seat all the way down, then screw it in, and as soon as the lifts start to rise, give the knob three more half-twists. This should have the throttles open about 1mm, which might be a little high for hot idle (1600 rpm or so), but is a good place to start.

Start bike with no throttle input of course! ...and dont be afraid to crank it for an ACTUAL 3-4 seconds.

GL!

TeK9iNe wrote:

9am53 wrote:

1. I have not messed with the screws at all...

2. I think I may be a bit lean since I went from stock exhaust to an open 4-1...

3. Is there a heat resistance sealant I could use to seal the interface between the carb holders and the head?

4. I thought these idles that don't come down at all are from the connection b/n carb and head leaking.

5. If there was one cylinder that was leaking would it cause the whole motor to rev?

6. adjusted knob on the back of the BS34s to lower the idle, it did nothing, and now it is all out of whack, is clockwise up or down?

7. Also, when the bike was reving like crazy I tried pulling on the choke and it just revved it up more, I thought maybe it might knock it back down, but it made it rev more.

OK...

1. Start messing with the screws. :laugh: With a 4-1 open pipe, I actually had to change pilots. (But mines huge). Start by lightly seating the screws, then back them out 2 turns for now, cause you don't want to $@#& around w/airbox, thats cool, and this should help.

2. YEP.

3.

Permatex® Form-A-Gasket® No. 2 Sealant

Slow-drying, non-hardening sealant designed for sealing cut gaskets and stamped parts. Allows for easy disassembly if required. Temperature range -65°F to 400°F (-54°C to 204°C); resists common shop fluids and fuels. Use where sealing is more important than adhesion.

Suggested Applications: Valve cover gaskets, oil pan gaskets. etc.

4. The air leak can be anywhere in the intake track, and cause strange undesirable result. For instance: I had a leak at the airbox boot and it caused popping on decel, and the idle to hang slightly when dropping the throttle...

5. YEP.

6. Idle control: Clockwise is raise idle, counterclock - lower idle.

7. It did this because it is relatively lean, and the choke supplied the required fuel to bring the cylinders up to a greater combustion potential.

Make sure to also check that the throttle components (ALL of them) are nowhere near anything that they could get hung up on. Like say a bit of hose clamp pushing up the throttle lifts on the front of carb... check all.


You did do a bench sync at least right?
To set the idle: Unscrew the idle control know until you can visually see the throttle lifts seat all the way down, then screw it in, and as soon as the lifts start to rise, give the knob three more half-twists. This should have the throttles open about 1mm, which might be a little high for hot idle (1600 rpm or so), but is a good place to start.

Start bike with no throttle input of course! ...and dont be afraid to crank it for an ACTUAL 3-4 seconds.

GL!

Thanks for the reply.

I have not done a bench synch, I thought since I didn't do anything with the carbs I could at least get around for a while and take it in to my tech to do (30$). Where are these screws for adjusting the idle air mixture? I will try to adjust them like you say. I will go get some of that permatex 2 stuff today and try it out. I checked for my throttle binding and it isn't. I didn't think it was though because the revving issue did not just appear, it gradually got worse as the motor warmed up.

Here's my gameplan (not for today though) I will adjust those air mixture screws wherever they are to 2 turns out, lightly smear some permatex around where the rubber meets the head (no pun intended) and turn the idle knob down counterclockwise. Is there an end to this knob spinning? or will it just spin forever?

btw, you say "start the bike up with no throttle of course" I habitually give the throttle a twist before I start, is this a bad idea? I don't know why I do it, I guess I will stop haha

9am53 wrote:

...turn the idle knob down counterclockwise. Is there an end to this knob spinning? or will it just spin forever?

Idle thumb screw will eventually unscrew itself from the carb and simply come out (like any screw being turned out of its threaded hole).

Meanwhile, with reference to racing idle, has proper functioning of the automatic advancer been verified by viewing its operation with a strobe type timing light?

Advancer sticking or tending to hang in the advanced position could cause the reported idle problem.

Good Fortune!

Might have already been suggested, but would also check integrity of vacuum hose to petcock (if so fitted) and end connections where the hose attaches to the carb and to the petcock.

Any air leak from a crack or poor connection could result in the racing idle, same as any other leak allowing outside air intrusion into the intake tract.

If not already done, would also check integrity of vacuum caps (plugs).

Good Fortune!

i have not verified it working properly, but will. It wasn't being weird before, and it was in good shape and I cleaned and greased it up, so I don't know if that's it, but I will check it out. The plan was to ride it for a little while, break in the rings and whatnot and then worry about all this stuff. That's cool.

I do have a dumb noob question though regarding the carbs, lets say the idle mixture screws are set too lean and I am running lean beacause of the tailpipe, wouldn't that just make it hard to start and run on choke only? How would running lean make it race uncontrollably?