So when I get back from school I plan on doing some work to my bike, it's not running perfectly and I'd like to get it there.
I'm going to check the valves, balance the carbs, and check the float heights. All things I've never done before.
Should I do these in any particular order? Or does it not matter?
I feel pretty confident about checking the valves and the float heights. But I'm still a little unsure of the whole carb balancing process, I have been searching and I will continue to search.
Quote from: bucks1605 on June 09, 2008, 04:13:38 PM
So when I get back from school I plan on doing some work to my bike, it's not running perfectly and I'd like to get it there.
I'm going to check the valves, balance the carbs, and check the float heights. All things I've never done before.
Should I do these in any particular order? Or does it not matter?
I feel pretty confident about checking the valves and the float heights. But I'm still a little unsure of the whole carb balancing process, I have been searching and I will continue to search.
The order
does matter:
1. float heights
2. valve clearance check
3. carb balance
You could probably reverse 1 and 2, but 3 should definitely be last. If the float heights are off, the engine may run rich/lean. If your valve clearances are out of spec, if may be difficult to balance the carbs.
There are a couple of links about building a homemade carb balancer (in the FAQ section, I think); I am assuming you have already read these? The carb balancing procedure is actually quite simple once you get your head around what is happening.
When air is forced through the carbs, each carb produces a low pressure region (vacuum) that draws in fuel to be mixed with the airflow. It is important that the vacuum be the same in both carbs so that the fuel mixture is the same and the resultant power produced by each cylinder is matched. If the carbs are not balanced, you will have one cylinder working harder than the other. This will result in less-than-optimum power production & delivery, and will lead to vibration problems.
To enable vacuum balancing, the design engineers have included a convenient test port on each carb. To balance the carbs, you connect each end of a liquid-filled tube to one of the test ports. This means that the vacuum pressure from each carb gets applied at either end. If the pressure in one carb is lower than the pressure in the other, it will pull the liquid higher up on its side of the "U" manometer. The carb balance is adjusted until the same pull is applied from each carb - this means the vacuum pressures are the same and the carbs are balanced. The important point is that it doesn't matter what the vacuum pressure is, only that the pressures are the same.
Thanks for all the info beRto.
I'm a big time visual learner and watching Kerry's video of checking the valves really helped me with that.
I've seen one picture of a home made carb balancer, but not any step-by-step how-to's. Your explanation of the logic makes sense, but I'm a little hazy on the actual process. I'll keep looking for some how-to's.
new plugs and a new air filter, oil + filter, replace all your fuel lines, blow out the over flow line, check the PCV line, all that jazz.
biggest help i've seen for smoothing things out is the valves + air filter, oil change. :)
oh, and clean/oil the chain ;)
Quote from: ohgood on June 09, 2008, 05:33:13 PM
new plugs and a new air filter, oil + filter, replace all your fuel lines, blow out the over flow line, check the PCV line, all that jazz.
biggest help i've seen for smoothing things out is the valves + air filter, oil change. :)
oh, and clean/oil the chain ;)
I may add that to the list, I did it late last season (oil +filter). But it's easy to do and it can't hurt. May get some new plugs, I'll have to take a look at mine. what's the PCV line?
positive crankcase ventilation(PCV) its a hose with a check valve that goes from your cylinder heads and goes to your air box. description it takes fuel fumes and sends them back to be burned in the combustion cycle. from what I remember from school :dunno_white:
Quote from: mach1 on June 09, 2008, 09:27:11 PM
positive crankcase ventilation(PCV) its a hose with a check valve that goes from your cylinder heads and goes to your air box. description it takes fuel fumes and sends them back to be burned in the combustion cycle. from what I remember from school :dunno_white:
That may be something that I need to fix. I have a K&N lunchbox on my bike, but I just have the stock PCV hose and it doesn't come close to reaching the filter, plus there is nothing on the end of the hose. I remember seeing somewhere that someone put some kind of a filter on the end, I'll have to look for that.
From the wiki
(http://i209.photobucket.com/albums/bb62/bucks1605/lunchbox.jpg)
This filter, K&N RU-2970, replaces both the drop in filter and the stock airbox. A breather filter, as shown in the picture, is recommended (but not really required due to factory steel mesh 'sponge' already under the breather cover) for the valve cover. This breather filter can either be a PVC filter valve (available at your local hardware store) or a breather valve like the one shown in the picture (available at your local auto parts store). The cheapest solution is a piece of shop towel covering the breather outlet to reject larger elements (sand, dust, etc). Keep in mind that the breather outlet is outbound, i.e. the combustion gases that get past the rings try to escape the engine case. BTW, that is the reason the breather hose in stock configuration is connected to the airbox -- to suck those gases out and back into the carbs to burn.
Quote from: bucks1605 on June 09, 2008, 09:35:50 PM
From the wiki
(http://i209.photobucket.com/albums/bb62/bucks1605/lunchbox.jpg)
This filter, K&N RU-2970, replaces both the drop in filter and the stock airbox. A breather filter, as shown in the picture, is recommended (but not really required due to factory steel mesh 'sponge' already under the breather cover) for the valve cover. This breather filter can either be a PVC filter valve (available at your local hardware store) or a breather valve like the one shown in the picture (available at your local auto parts store). The cheapest solution is a piece of shop towel covering the breather outlet to reject larger elements (sand, dust, etc). Keep in mind that the breather outlet is outbound, i.e. the combustion gases that get past the rings try to escape the engine case. BTW, that is the reason the breather hose in stock configuration is connected to the airbox -- to suck those gases out and back into the carbs to burn.
That's the set up I have.
Here's what I found, cheapest thing they had. Everything had chrome on it, so of course you have to jack up the price... :icon_rolleyes:
http://www.autozone.com/R,NONAPP1003/store,1796/initialAction,accessoryProductDetail/shopping/accessoryProductDetail.htm (http://www.autozone.com/R,NONAPP1003/store,1796/initialAction,accessoryProductDetail/shopping/accessoryProductDetail.htm)