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Racey Rider
28th February 2004, 18:22
So I's got me a cheap Kawasaki KR150 with a ticking noise in the motor. Had my first forray into streetstock racing last winter and are keen to get this KR sorted and do the full Vic series. I brought this bike because it was cheap, and it matched my leathers!
(What other reason do you need?) :niceone:

Being a little mechanical, and on a tight budget, I'm diving into fixing the bike up myself. Stripping all the unnecessary stuff off the bike is always fun, and helps to be able to see exactly what you've bought.

The main fix would be that ticking in the motor. A "somethings definitely wrong" sort of ticking. Bought the bike knowing that it may need a new piston kit or something so, was expecting to spend another $300 odd dollars on that, and end up with a fresh motor to go racing with.
Unfortunately the budget doesn't allow to get the shop mechanics to do the job, so it's me and ... the dedicated advice givers at KiwiBiker, to attack the project.
( Yes, yes ,,, I'll mention your name when I get on the podium!) :rolleyes:

So, a 99 KR150, Single cyclinder two stroke ... how hard can it be?!

After a compression test, (130psi), I started dismantling everything around the motor. Have layed the radiator down and filled with water, as read somewhere they shouldn't be left to dry inside, as it allows the air to develop rust in them. (Any thoughts?)

Thought I should get the flywheel off before removing the motor from the frame. What a mission getting that flywheel nut off! Had to use a rattle gun in the end, which took about 2 seconds. Then had to get a special puller to remove the flywheel. Once done I could undo the last bolts and remove the motor from the frame. Stage 1 complete!
:apint: (well ... a coffee anyway!)

Today was the "take the motor apart" Day. :banana:
Pouring with rain outside, noisy kids inside! New flood lights in the garage.
What shall I do today? SEE YA! (Don't worry, She had the morning in town to herself!)
Set up a table in the middle of the garage ... plonk motor on said table ... and start to dissect it! Out come the reeds first. They look fine, but a little bit of metal filings around the area. Not a good sign.
I decided to leave the head on, and expose the piston by removing the cyclinder. The cyclinder showed quite an area of scratching around the intake side. The 2 rings were still in one piece, but the piston had a chunk missing from it's skirt. The top of the piston had a flattened top edge in one spot.
I presume, as the piston travelled up the cyclinder, not perfectly square due to the broken skirt, it was hitting the top of an exhaust port, thus making the ticking noise.
So new piston and rings it is!
What else should be changed while am there? Top end bearing? con rod pin?
Should honing the cyclinder remove the light scratching, or does it sound worse than that? Re the metal fileing, was thinking of spraying some deisel around inside the crank case to help wash this away. Thou I can't see anything much in there. Is there a better way? :spudwhat:

So stage 2 is well under way.

What else needs doing.
Have taken the triple clamps and forks off as the streering bearings are a bit notchy. There seems to be two of the bearing races left in the frame stem. Do you just beat these out with a screwdriver pushed through from the opposite side or what?

Brakes: have got the pots out of the brake calipars to clean them up. Is fine sandpaper alright to clean these up? Should the O rings that seal the pots in the calipars be replaced or just leave as is?

Anyone know if I'm required to have an air filter on the bike for Streetstock racing?

I'm gonna try the "ride it like you stole it" run-in approach, so will let you know if it develops any immediate problems.

Wish me luck in getting it all back together!
Racey. :scooter:

Andrew
28th February 2004, 20:31
Talk to Dave. I've seen him do this sort of thing each time he does a re-build of his 125's. He'll know for sure!

speedpro
28th February 2004, 21:12
That piston is well used, check the brown stains below the rings. It's just about definite you will need to rebore. If you have metal filings floating round inside and you don't want to dissamble the crankcases which you should, you could slosh some engine degreaser inside the crankcases. This will dissolve all the oil and free any debris. Then jam the garden hose in and flush the whole lot out. Drain the water as best as possible and give it a good dose of WD40 or CRC. Oil it good before reassembly. If you are thinking of doing more of this work yourself get a torque wrench, it'll save all sorts of dramas later like stripped threads or blown gaskets. For getting old gaskets off rather than use a scraper and risk garking up the alloy give it a dab of oven cleaner first. Spray it into an ice cream container first and then put it on the gasket with a little paint brush. It'll bubble away and make the gasket easy to remove. You must wash it good afterwards. DON'T get it on paint.
Keep anything with grit away from the brakes. Spotless attention to detail is required here, if you have any doubts just remember the situations where you'll need your brakes the most and then imagine them failing. :doctor:
Ask lots of questions , , , oh , , you're already doing that.

Dave
1st March 2004, 09:22
Replace piston,rings,clips,pin and small end bearing. Check the manual and see what milage the crank needs changing at.
If its a plated bore then DO NOT HONE it. If it has aluminium stuck too it anywhere, use some wet and dry 800 grit and polish it off, (could take hours).
New reeds,check the clutch.
if you do the crank,then fit new main bearings as well.
If it all turns to shit-package it up and send it too me. Yes i will charge you, but it will be done properly!

FzerozeroT
2nd March 2004, 09:02
one thing to remember, the ring pins that stop the rings rotating, had a mate rebuild an RM 125 and not check this, "bit tight to kick start and doesn't make the same power", whoops, ANOTHER rebore and rings :eek:

Racey Rider
3rd March 2004, 20:16
Have been told by two mechanics that the barrell is stuffed. Doesn't seem that bad to me, but what do I know!
Has some slight scratching around the bore, and apparently, as it's "plated" can't be honed or rebored.
So options are:
Get it re-sleaved and bored to the orginal size - about $400.
Send it overseas to get re-plated - $530
Find a secondhand one - $???

But as I say, It doesn't look that bad. What would happen if I just took to it with some sandpaper and then chucked new rings/piston in it?
Sure it may not be 100%,,, But wouldn't it still be 99% !?
Motors still run when ther're in bad condition, wouldn't the new rings just wear to the wear off the cylinder?
Of course a real mechanics go'na say it shouldn't be done,, It can't be done!
cause the've got a reputation to protect.
But I'm a man of "No Reputation"! 99% is good enough for me!

What I want to know is,,,, How badly are you laughing?!

Little laughing,,, yer, it might work. :D

Lot of laughing. Should be good for ONE LAP! :lol:

Kwaka-Kid
4th March 2004, 04:51
I Personally would just do it :P but i know NOTHING and my advice shoud not really be taken :) but a big thumbs up to you RR for doing it all yourself! im the same only have no mechanical knowledge :p

Motu
4th March 2004, 06:43
Take a look in Bike Mart(inside Kiwi Rider) there is an add for Electrosil,they replate barrels - 18 day turnaround,looks like it's something to do with Te Puke Farm and Trail.With an 18day turnaround I'd say it's going to OZ.

Dave
4th March 2004, 07:29
Just clean it up with wet and dry, like you say, it will be down on power slightly-but will still run o.k.

Racey Rider
4th March 2004, 07:59
I Personally would just do it :P but i know NOTHING


Just clean it up with wet and dry, like you say, it will be down on power slightly-but will still run o.k.

Well there you go then! I've been given the go ahead by two titans, at totally different ends of the mechanical reputantion line!
Sounds good enough for me. Maybe i"ll change the barrel next time.


Take a look in Bike Mart(inside Kiwi Rider) there is an add for Electrosil,they replate barrels - 18 day turnaround,looks like it's something to do with Te Puke Farm and Trail.With an 18day turnaround I'd say it's going to OZ.

I rang that guy. he's an agent for a Oz firm as you say. $530 back on my door step. Thanks.

Racey Rider
4th April 2004, 18:28
Finally I got some spare money to get on with this project.
I ordered a Piston kit, with the idea of useing this slightly worn looking barrel for the mean time. But about the sixth time I looked at this old cylinder barrel, I noticed a broken port bridge, of a size you can fit your finger in. :argh: Trouble is, I can't find a secondhand barrell for the bike.
As it wasn't in the buget, and the motor was running fine before, (other than the ticking noise), I thought let's just stick it back together and see how it runs till I can find a replacement. :rolleyes:
So in went the new piston with the old rings on, old pin and bearing. At least if it all turns to custard It's only a $109 piston I loose not the whole $230 kit.
So motor goes in, bits go on,,, comes the big moment.
Fuel on. Key on... For your own saftey, take one step back from your computer before I throw a boot at this thing! :sweatdrop

RRrrinnnnng ding ding ding ding ding!
"KK would be proud" I thought as the little motor setteled into a calm idle. :banana:
So she goes! Yes it sounds a little ruff as the rings ajust to the half sanded barrell. Yes it still may only make it round half a lap of the track. Yes the broken port must be affecting the power output. But I'll be there at the first round of the Manfield winter series (17th April). I'll be trying to pick up that valueable 1 point for comeing second-to-last in the last race of the day!
Who knows,,, That 1 point may be all it takes to finish in front of the next guy at the end of the season (by which time I should have my motor sorted properly!). :Punk:
Racey

pete376403
4th April 2004, 19:32
Which port was the bridge broken? The bridge prevents the rings from bulging out into the port, so its not really optional, especially if its the exhaust port.
However it sounds like you're doing fine so far, and learning, which is the main thing.

Kwaka-Kid
4th April 2004, 23:41
Good stuff racey! and heck yeah im proud! thats great news, with a bit of luck shell hold out yeah!

F5 Dave
5th April 2004, 17:37
If the plating is worn through then you will be running on Ally & that is just begging for a seizure. The broken bridge may also expand out, get a good yank & cause some real damage. 2nd hand rings will lose power as well.

Most places that do replating also do barrel repairs if they aren’t too far gone.

Kickaha
5th April 2004, 19:52
I rang that guy. he's an agent for a Oz firm as you say. $530 back on my door step. Thanks.

Ther are two firms at least in OZ that do this work,one of these firms rooted a 99 TZ250 kit barrel that was sent to then,it was so bad it had to be scrapped.

A guy down here deals with a UK crowd time around time is slower but they do a top job,he's a aircraft engineer so is a fussy prick and for a replate without any repairs was a bit less expensive.

Racey Rider
11th April 2004, 16:07
Which port was the bridge broken? The bridge prevents the rings from bulging out into the port, so its not really optional, especially if its the exhaust port.

Yes I was aware that might happen. Fine so far, but early days yet.
It was a rear/side port bridge between the lower transfer port and upper KIPS valve exhaust port.

Racey Rider
11th April 2004, 16:16
Yesterday I got the final bits I needed to start a better test of the bike.

Things done to bike:
Steering head bearings - bearings were very notchy, so wanted to replace them. Took the triple clamp off, dropped the fork stem out and found the bearings come apart in pieces.Top race, individual balls and the lower race x2 pressed into the frame took a lot of bashing to get out. they were rather pitted so went off to check price on genuine Kawasaki replacements. Kawasaki sell each item separately. $74.25 for the four bearing races + the balls @$1 each. Must be a cheaper option. Checked the local bearing places. No one had the same type. Still, I’m not paying $100 odd bucks for OEM parts. So I find a bearing thats close, (1mm to big in the centre), Which I pack with a bit of hose clamp. Top bearing race just couldn’t be found, so ended up sanding the pits out and reusing the old one with new balls in it, (But not @$1 each I can tell you!). So steering is sorted. A little tight at the moment, but better that too loose. :doobey:

Brakes - Callipers were pulled apart and brake pistons cleaned up with sandpaper. The seals were price at $118. PARDON ME!? Yes $118 for 8 little pieces of brake rubber seal stuff from Kawasaki! GET OUTA HERE! :bash:
So off I trot to the brake seals shop. “ No, they’re too small. We can’t get anything that small.” Luckily one guy suggested to try Brake fluid resistant O rings. So the local Gasket/seals shop measures and orders some for me.
‘How much Mate”? $4.80
PARDON ME? $4.80. Now That I can handle.
So far they’re working fine. Through some new pads in the front. All good! :yes:

Tyres - Front tyre is in good condition. Bridgestone BT-39 ss. Rear a Dunlop K275A bit worn through the centre and flat with 3 tubeless puncture repairs in it. My plan was to change the rubber over to the TT900s I had from last years bike. Already quite worn, but at least I know what grip to expect from them. Don’t know anything about the grip of these current tyres. But after removing the rear tyre from rim, I found the wheel to be 18” and my race rubber wouldn’t fit it. :doh: No money for new tyres, so I had to put a tube in the rear and make do. First tube got recked due to bad tyre leaver technique. :doh: :doh: Better luck with number two. The other problem was the tyre wouldn’t sit on the bead right so was quite out of balance. I now realise I should have used soapy water to help it settle into position.

Engine test - I knew the motor was running alright at idle but it was time to test it at full rev’s. Had started it with premix in the tank, but was keen to get the auto oiler working again, (As I had removed the two/ oil that came with it) so changed to straight 91. Doing some slow runs up the road at half rev’s started well until that depressing feeling of the motor jamming up, the back wheel locking up, then freeing, then locking up again. Not goood! :sick: The motor still ran and got me home, but I wasn’t sure what was happening. The next day I donned all my race gear and went to try again, (Hopeing the bike had fixed itself over night,, as you do!). :yes: Sure enough, soon after I picked up the rev’s, and the motor started doing some work, same problem,,, seising up. :disapint: It didn’t feel like the problem was being caused by my broken port problem, so I guessed maybe the oil wasn’t getting through. A check of the oil pump area showed air bubbles in the lines, so that seemed correct. I reattached the premix flow and let the engine run and rev a bit till I was happy the auto oiler was flowing properly. Re-attach the main fuel and go for another run.

Conclusion - I’m happy to say, the bike ran well from then. Slowly built up the rev’s till it was pulling at the red line. No problems.

Man have I learn't alot!

The bike definitely is down on power, (Broken port window, old rings), and yet is running well, (At this stage). If it lasts on race day it will be a good opportunity to practice keeping my corner speed up, (if the tyres are up to it). If it gets through the whole day I’ll feel it’s been quite an accomplishment.

Just goes to show what abuse a two/ can handle.

Thanks for being interested!
Everyone keep an eye out for another barrel for me. 99 KR150.

Will let you know what happens.
Racey :cool:
#41 Street stocks.

Racey Rider
20th April 2004, 22:12
Race day ---- Let me see,, where do I start.
How about the end!

Last race of the day, The little KR is singing away as a happy sewing machine should. Halfway through the race, what do I spy out of my little eye???
Dave,, Parked up in the middle of the paddock, with his RS125. :spudwave:

Dave, Dave, Dave! :not:

You know Dave!?


If it all turns to shit-package it up and send it too me. Yes i will charge you, but it will be done properly!

That Dave!

The checkered flag falls, and the KR gets a pat on the tank for getting me through the day. As I pull in through the dummy grid, there's Dave telling his Mrs what had gone wrong. So I pull up next to him,,,,,, (Well,,,, It had to be said!),,,, "YOU JUST SEND IT DOWN TO ME DAVE. AT LEAST YOU'LL KNOW IT WILL BE DONE PROPERLY!!!" :buggerd: :killingme


The Begining.
A Beatiful day at manfield. My first time on the long track. Saddly my motor wasn't as good as could be, but at least I was out there!
The first couple of pratice session had me concered about a unstable front end. It wanted to weave all over tha place in corners. I tighten the steering head bolt and added air to the front tyre which for the second pratice felt better. I then made a bad mistake. Before race 1 I tighten the steering bearings down hopeing to improve the feel more. unfortunitly this made the problem 100 times worse. As soon as I rode down pit lane, I could feel it so tight I had no control. It was too dangerous to race, so had to miss race 1. :doh:

Got it sorted somewhat for race 2. Just as well there was a newbe in my class who gave me someone to race against, as everyone else just took off. Even the smoke had cleared by the time we got to the first turn. But I had fun riding around the outside of this guy in the corners, while he pasted me on the straights.

Good points: The motor lasted all day. :banana:
the cheap O rings in the brakes worked great! :2thumbsup

Bad points: Steering bearings still need work.
Tyres wouldn't heatup. Might work better when I can push them harder.

Hoping I can get my motor sorted properly before the next round.
If I have time after fixing Dave's bike that is!! :laugh:

See ya out there!

This has been:
Racey Rider :cool:

bungbung
21st April 2004, 08:44
Hey RR, I got tapered roller head bearings for my VTR for $68 from www.schrodoco.co.nz branded "all balls racing".

Give them a try.

Racey Rider
8th January 2005, 19:32
So it's been almost a year since I brought this bike, and finally, I’ve got it sorted. :2thumbsup

While down for the boxing day races, I called in to see a chap with another old KR150 that had been crash damaged. Looked like a pile of junk, But to me, it was the much sort after barrell.
Having priced a new barrell at over $900, and having a hard time finding any secondhand one, the only other option was to send my broken port window barrell to Ozz to a Electrosil barrell fixer. $500 + apparently.
(re-sleaving didn’t sound like a good option).

I had seen 1 Kr go on the net for $750. But as this one had high K’s and was looking battered, I told him my best offer was $500. The fact that we couldn’t get it to start on the day helped him accepted the deal. So $500 got me a barrell + lots of other spares. :niceone:

On getting it home I clean out the carb, dry off the spark plug, and give it the kick. RRrrinnnnng ding ding ding ding ding!
Take it for a quick run. Sweet!

As the kick starter is worn out on the new bike, I decide to removed the barrel and install, with the same piston and new rings onto my old motor base.

Had a good look at the barrell once off. 46000km and it still looked good. Had no tools to measure for wear, so just had to hope that “looked good” would be good enough. :yeah:

One funny thing I noticed when checking out the bike, Some Wally had put 100psi in the front wheel! :shit: Had "42 psi Max" written on the tyre. Some people have No idea!! :no: Rear had 60 odd psi.

So have fitted barrell with new rings into my KR. Oiled everything up as it all went in. Then got the Family out to witness the first start up.
After a few kicks to get the fuel through. RRrrinnnnng ding ding ding ding ding!

Well I’ll be a GP mechanic! :spudbooge That sounds just like a new one!

Do a few checks, No water leaks, still plenty of water in the radiator, idling nicely,,
Let’s RIDE! :ride:

Donn some basic gear, and head out onto the err, , “test track”.
Give it some warm up time, then go with the “push it hard” run in approach.
Took it for a 30km run, revving hard up to 9000 rpm (redline 10500), then dropping off the rev’s, then making it pull hard again, then off. All good.

Today I gave it a harder workout. Allowing it to rev right up to redline. But since as it is in race bike mode, couldn’t take it for a long run. Motor sounds good, but hasn’t reached the top speed I was looking for yet. :blink:
Maybe that’s cause of the contour of the roa... “test track”, or the wind today, or as I was useing oil injection and pre mix at the same time for the first 5 litres, or maybe after only 50km, the rings need to free up a bit more. Hopefully once I get to Manfield I’ll have a better chance to see if the motors
up to race pace.

If I can come up with the money I plan to do the Manfield winter series.
:ride:
See ya out there.
Racey.

sAsLEX
8th January 2005, 23:13
good shit mate!!! sounds as though your having fun! oh and cheers for taking the CBR up to auckland al those monthd ago!

Kwaka-Kid
9th January 2005, 08:02
YAY RACEY! Good stuff dude!

cant wait to finally catch up with you at the track sometime dude!

gav
9th January 2005, 09:40
Great posts!! Keep up the good work. :2thumbsup
Got any photos of the beast?

Coyote
9th January 2005, 10:19
If I can come up with the money I plan to do the Manfield winter series.
:ride:

When does the season start? I hope to enter if I can get some more info on when and how much

Racey Rider
10th January 2005, 20:27
Great posts!! Keep up the good work. :2thumbsup
Got any photos of the beast?


Blue Thunder


http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=6388

Motu
10th January 2005, 21:13
You got lottsa legs mate...two sets look atrophied,I don't wanna be rude,but were you born like that?

Ghost Lemur
10th January 2005, 21:30
Looking good RR.

But what's the deal with the kneesliders stuck on the jeans.

I'd say it was a very KK looking piece of kit, but the kneesliders look too pro. *jks* :lol:

Racey Rider
11th January 2005, 06:16
You got lottsa legs mate...two sets look atrophied,I don't wanna be rude,but were you born like that?

If find if I race with the kids onboard, they can put their feet out and push us through the corners.


Looking good RR.
But what's the deal with the kneesliders stuck on the jeans.
I'd say it was a very KK looking piece of kit, but the kneesliders look too pro. *jks* :lol:

Alright! Let's make it offical.
RR refers to Riff Raff.
Racey refers to Racey.

They'er not actually "kneesliders", but advertiseing hordings. That's why I keep them so new and shiney. That sponsership deal is gunna be rolling in any day now. As for what keep me up in the corners, see above.
Ha! Honda boy would be so lucky!
Racey. :cool:

Kwaka-Kid
11th January 2005, 17:12
Oi! Fine Racey you just lost out on the whole RR initial thing :(

but anyways dude good work on the bike! WIIICKED :D and are they really jeans? plase say no as that was my idea and has been for a good 12 months now!! :)

FROSTY
11th January 2005, 17:28
good onya racey -double thumbs up--ya gonna be out there racing and ya riding a kwakka. :2thumbsup
But MAAAAAATE --get with the program alll KB bikes gotta be yellow--to shoy loyalty :Oi:
ASk me KK or SVS
bugger this one finger typing shite :ar15: