Project 175

[actarus]

Hi all !

I am now the proud owner of a 1980 KDX 175 !! First dirt bike at 30 can you imagine :laugh:

I think for it's age it is pretty clean ! Kick starter lever died same day I got it :yikes: and is now under repair. The chain is maxed out and the adjustments a all out too so I guess it'll need to be changed. I was wondering if something like bring back the adjustments all the way in and shorten the chain a link or two is something you'd recommend or changing it is the thing to do ?

Have'nt inspected rear and front sprokets. Engine still runs fine idle but still wont go forward without stalling right after. I've been suggested it could be a carb issue or gas line being clogged or some seals letting air in in the engine. What do you think of that ?

In the service manual it is said to have the gas mixed at a ratio of 20:1 Don't you think it's a bit rich on the oil ? After reading ... it has been recommended many times to run a 32:1 ratio ... would that suit my bike ? But then again ... I don't want to rejet or anything.

Well I'm still reading the just kdx and learning a ton !! Awesome amount of info in here :cool: Keep up the good work guys !!!!

 

[yankeefan4life72]

welcome!!What did you pay for the bike??You will have a blast on a kdx!!

 

[actarus]

Paid 350$(cad) for it and i think it really is wort what I paid for it :nod: ;)

 

[kdx175]

Hey, hey nice bike you've got there. Don't worry about running 32:1, thats what ive ran in my 175 for the last 3 years with no trouble at all. As to the chain, I realy recomend bying a new one. If it happened to brake it might brake the case (bad news!). Mine has been wicked dependable and a blast to ride :aj: . For a 24 year old bike it keeps up pretty good to the new stuff. :) mine still has the original top end!!

 

[actarus]

kdx175 ... did you rejet or anythinig to run it 32:1 ?

I figured, since I will need to buy many parts, the chain will be changed by an o-ring one in the process :cool: and probably be able to get a better price ;)

 

[dante]

I bought an old bike once and it would start right away, and idle fine but once you started rolling it would bog really bad and die just the same as that bike... check the compression, I bet the person sold it after trying everything already, but it actually just lacks compression something allot of people are just in denile about... do a top end and i bet it will scream...

I've had the chain thing happen to me before too, pop out two links it'll be fine until you get cash together to sort it out... also while the chain is off soak it in gas, clean it really really good, then lube it up, and reinstall with a freah master link...

 

[actarus]

Wow thanks a milion for the advise !

I've taken out the carb to have it cleaned and after opening it I saw it was a pretty good since it had some residue in the bottom where is the main jet cover located and elsewhere in the carb. When the carb is back surely the kick pedal will too. Then I'll try to fire it up and see for myself what really goes on with it.

Thanks again ... it IS appreciated :cool:

 

[Colorado]

You can get a factory service manual online for between 10-15 $US. Your compression service limit is 118, but someone here recently posted that there '82 has 150lbs.. I paid $500US for my '80 175, but it ran enough to ride. It's a fun bike, and pretty fast (after I fixed a leak at the intake boot).

Ther tank when I bought it leaked at the mounting bracket. I bought a used one, cleaned it all up, then found it leaking at the horizontal line along the bottom. I think it's a weak point for them. Found a used Clark tank to put on it, but the petcock was broke, so I'm still getting wet right knee when I ride. Maybe I'll find the petcock this week.

 

[actarus]

The guy who sold me the bike gave me the service manual in the same time ... witch is a real gole mine for me. All that's left for ma is to test the pressure builting in the compression chamber when I get the carb back from cleaning and the repaired kick lever in place and when I can find presure meter :nener:

 

[actarus]

Well ... got the kickstarter repaired (had to buy a brand new boss) and now it is kicking ... just that. won't start at all. The plug gets wet, there is a spark and compression is good (~115 lbs). Only thing that is buggine me though is that there is a pretty good amount of gas leaking from the carb. Could be the cup gasket but I'm wondering if it could be the way I've reassemble the valve throttle.

What do you guys think of that ?

 

[Colorado]

Well ... got the kickstarter repaired (had to buy a brand new boss) and now it is kicking ... just that. won't start at all. The plug gets wet, there is a spark and compression is good (~115 lbs). Only thing that is buggine me though is that there is a pretty good amount of gas leaking from the carb. Could be the cup gasket but I'm wondering if it could be the way I've reassemble the valve throttle.

What do you guys think of that ?

Leaking where? Through the overflows? If so, check your float adjustment and make sure you put the float needle parts and floats themselves back in correctly. I haven't been through my KDX carb yet, but just did two carbs from late '70s Yamahas with basically the same Mikuni (except bigger). If you soaked all of your jets in carb cleaner, then blew them out with compressed air your problems are almost surely in the float system. Start out with your main needle clip in the center groove too, or one groove either way. If I remember right, the third one is the stock setting, and is the center one. I replace O-rings with standard ones from an auto parts store instead of paying motorcycle part prices, and I re-use gaskets if they come off in one piece, but use a gasket sealer on them.

115lbs. is just below the recommended service limit on the top end, but you still ought to be able to get it running. If you've got a good spark, keep concentrating on fuel delivery until you figure out the leaking and are confident everything is assembled right.

Regarding the chain, if you replace it you really should do the sprockets too, particularly if you spring for the good one. Old sprockets will wear out a new chain quicker. Also, if the chain is stretched beyond it's service limit it has probably trashed the sprockets. They shouldn't have pointy teeth, and the sides of the teeth should look symetrical, not worn on the side that the force is delivered to. Unless you're ready to spring for all three parts I'd go with a regular chain and plan to do it all right the next time, after it's running good and you've decided if you're going to rebuild the top end or just ride it as long as it lasts.

 

[actarus]

Some droplets are coming from the cup and some goes through the overflow line (the longest one). But I just remembered that I probably forgot to put back a piece in the carb and that would be the needle jet holder. Could that be related in anyway to what I've described earlier ?

 

[MX175]

Chain/sprockets: you can live a little longer by shortening the chain, but I would plan on replacing both sprockets and the chain at the same time and in the next few hundred miles. As previously mentioned, a broken chain that destroys your engine case will ruin your day.

Carb: This is likely why the bike won't run. If you are leaking fuel, there is probably also fuel leaking into the cylinder and causing an extremely rich condition. There are two things called needles in a carb. One is attached to the float and consists of a "needle and seat". This needle attached the the float is about 3/8" long and is usually brass, possibly with a rubber tip. When the float forces the needle into the seat, it stops the flow of fuel from the gas tank into the float bowl. These do wear and it is likely to be your current problem. You may want to replace the needle and seat.

There is also a "needle jet" that is the longest brass piece, in the center of the carb. Usually the main jet threads into the bottom of the needle jet. A long (about 2") round "needle" (aluminum?) in the slide, runs inside the needle jet. These probably have nothing to do with how or why your bike is not currently starting.

Hope this helps...Keep those 175's alive.

 

[actarus]

When I first thought to take the carb apart and clean it I thought about changing that precise part but unfortunately that part is no longer available from Kawi. Is there some place on the net I could get it from. I found it available on the oem section of the bikebandit site but since I'm in canada without a credit card ... it can be pretty tough ordering stuff over the net ....

I'll keep looking though !

As for the chain, I think I'll go for the shortening suggestion and see how it goes from there.

 

[Green Hornet]

If kawa does'nt have-Bike bandit can't get either. You might have to get an aftermarket carb.

 

[Colorado]

It's not impossible to recondition the needle (float seat one) with fine emory paper to some degree --- probably at least enough to help diagnose the problem. The float needle also springs on a 'plunger' (?). MY 175 has a second carb on it (not for aircraft use according to the sticker). The original one is on my bench, but I don't remember what part it was that the last owner said he couldn't get.

You remarks about a needle jet holder aren't very clear. The needle is one thing, and the needle jet another. The main jet screws into it, as MX175 pointed out. If you left your main jet out you'll get a really wet plug and the bike won't start.

Edit: I don't think it would explain the leaking though.

 

[actarus]

*Update*

It finally fired up ! What a relief ... after about 3 week of working on the bike ! Now I just ned to shorten the chain, replace the muffler joint and go ride to determine if it will need a clutch job or not.

 

[Colorado]

*Update*

It finally fired up ! What a relief ... after about 3 week of working on the bike ! Now I just ned to shorten the chain, replace the muffler joint and go ride to determine if it will need a clutch job or not.

Cool!

I was wondering how things were going. What was the fuel problem?

I got my new petcock. MY 175 needs a little jetting adjustment. I was trying different things before I discovered the air leak caused by a stripped intake bolt, so now need to start over again. I got sidetracked on an MX400 that I picked up for $350, and today I need to catch up things on the house or I just might have to move out to the shop.

 

[actarus]

I think that the problem is due to when I've put back the carb on the bike. It seemed tha I had inserted the valve/throttle. I don't know how I ended putting it back the wrong way :coocoo:

Anyway, everything's back to what it should be, chain shortening will probably be on sunday or monday with the o-ring for the muffler(that is if they have it in stock). If I can't get from my kawi dealer, I'll go get it from a car shop ! :rotfl:

I'll keep you updated ;)

 

[actarus]

*Update*

Chain is shortened (2 links) but what puzzles is that o-ring for the muffler. They did'nt had it in stock, of course, so now I have to wait until tuesday for the part to arrive.

Do you guys know of a temporary solution that I coule use until the original piece arrives ?

The o-ring (I don't konw what it's made of but surely not rubber) goes on the end of the muffler that plugs on the engine.

 

[Colorado]

*Update*

Chain is shortened (2 links) but what puzzles is that o-ring for the muffler. They did'nt had it in stock, of course, so now I have to wait until tuesday for the part to arrive.

Do you guys know of a temporary solution that I coule use until the original piece arrives ?

The o-ring (I don't konw what it's made of but surely not rubber) goes on the end of the muffler that plugs on the engine.

You COULD ride without it. It wouldn't be the end of the world. Little smoke and splooge, but, HEY! I bought a KX125 O-ring set for my 175. It was in stock and looked close --- and was close enough.
:cool:

 

[Colorado]

Oh yeah ---- and it is rubber! Maybe some special kind. You'll have to ask someone else.

 

[actarus]

Well "god" was on my side today ...

The part came in this afternoon and in deed, it is rubber ... go figure lollllllll

Anyway, I'll try to put back the chain and the o-ring tomorrow if not it will be on saturday. After that, first test ride :cool:

I don't know if I'm too impatient since it has only been a month that I bought the bike ... nah I think not ... :nener:

Until next update !

 

[actarus]

*Update*

Today got the chain back on, installed the o-ring on muffler but couldn't ride ... again ...

There seems to be a clutch problem now. The bike won't even get in first without stalling right away ... :( :pissed:

I played with the adjustments well enough I think ...

I guess it's obvious now that I will have to service the clutch.

 

[Green Hornet]

My old KDX would get clutch weird now and then. Take a rubber mallet and gingerly tap the gear shifter and clutch cover. Remember gingerly, not pissed off gingerly. See if that helps the sticky situation. If not then take apart