Thanks for everyone's help over the last few months. I got the bike to a point where I could start it. No chain or brakes yet... lots of wire placement stuff to do but it started on the third kick after being in a million pieces. Its on premix at a little more than 32:1 which is what I run in my YZ125 so I just went with that. I still need to finish priming the pump and all that. I put the stock points system on it at 1.8 btc even though I have an HPI ready for it. I wanted to get it running as good as possible 100% stock as it was when it was sold before changing the iggy. I want to feel the different between the two. I still need to get a proper exhaust baffle for the one side... I have no clue where the one that's in there is from.
One thing I noticed at this ultra early stage is the bike quickly settles into idle after a blip of the throttle. All my other 2 strokes never did that remotely as quickly... probably because they all had air leaks and I never knew it. This bike got the leakdown treatment.
https://www.bitchute.com/video/vSc0w1C73SGS/ (https://www.bitchute.com/video/vSc0w1C73SGS/)
Always feels good to get that first start. I'm interested in your HPI comparison!
Sounds Awesome, Good Job :clap:
Congrats. That is always an exciting moment on each bike! :metal: :taz:
Nice work! :clap: Success (project progress) always feels good
Congratulations! :cheerleader:
If I may make a suggestion that you may already be aware of; test your pump for proper output after you run it for a little while. Mine was working fine and then one side pretty much quit putting out, and the other just put out a little bit. Caused a seizure. :bang: Wish I'd have had some oil in the tank! :twocents:
Quote from: Greaser Greg on March 06, 2020, 07:36:19 PM
Congratulations! :cheerleader:
If I may make a suggestion that you may already be aware of; test your pump for proper output after you run it for a little while. Mine was working fine and then one side pretty much quit putting out, and the other just put out a little bit. Caused a seizure. :bang: Wish I'd have had some oil in the tank! :twocents:
Thank you for that heads up and it's a good idea for me to make sure it is functioning as intended. After all the weird stuff I found done to this bike I didnt want to risk using the pump right away which is why I have it on premix. One of the issues I discovered was actually with the pump... it had 2 washers at the end of the worm gear causing it to almost bind. The white plastic gear was very stuff to turn and I knew it shouldnt be so I investigated and found the extra washer. Good thing too... no way that gear would have survived too long.
To test the pump do I just pull the cable out on high output and make sure I see oil pumping in both lines equally?
There's a testing procedure where at a specific rpm you should have output if a certain mL if oil. I'm not 100% what that is though. I do believe in Chuck's corner he has a test he runs?
Search for autolube test. There's a specific output for each pump at 200 turns of wheel. I think it's around 5.3 cc out of each tube for R5, but don't quote me!
After the pump is rebuilt.
The test I do is to make sure both sides pump the same.
Then you have 2 options from there to adjust the output.
1st is the pump shimming.
.008-.009 in. is what I use for stock bikes.
On my hotrod builds...
.011-.012 in.
The other adjustment is cable timing.
On good high end modern synthetic oils you can retard to 3mm
at wide open timing. (stock carbs at 28mm pull)
http://www.2strokeworld.net/forum/index.php?topic=1119.0
Chuck.
Congratulations on first start.
In a hurry you can disconnect the lines at the carbs and zip tie the nozzles in small bags to to collect the oil. Make sure you plug the carbs, secure the bags not to lose oil and run premix in the fuel tank.
i don't recommend this method to measure specs, but it is a good start to make sure both sides are pumping somewhat equal.
Good thing you guys suggested I check the pump :bang:
I did like I saw in Chuck's vid and had two long hoses strung up so I could compare the two. Sure enough something was up. One line had tiny air bubbles in it with each pump that didnt go away after a foot of tube had filled up. The other side was all oil. Then I noticed a drip... looks like oil was slowly escaping from being that white wheel you turn by hand to prime.
There's a reproduction and a Yamaha oil pump rebuild kit at Econo... any thoughts on which one I get? It seems the repro has extra seal in it.
Thanks again guys.
Pretty sure the repro has a seal for a different oil pump. The one economy sells has check valve rebuilds for the nozzles too.
I found the shaft has a plug in it that had come loose. The seal wasn't leaking above the wheel, but oil dripped out from the center of the shaft. It's a rubber plug with epoxy holding it in. Seemed to seal ok just being shoved back all the way up, but haven't tried to run one that way. Someone on here used jb weld to hold it in the shaft.
How are the brass nozzles removed for inspection of check valve balls and springs, heat on pump body and twist the fitting?
Quote from: Greaser Greg on March 08, 2020, 10:36:08 PM
I found the shaft has a plug in it that had come loose. The seal wasn't leaking above the wheel, but oil dripped out from the center of the shaft. It's a rubber plug with epoxy holding it in. Seemed to seal ok just being shoved back all the way up, but haven't tried to run one that way. Someone on here used jb weld to hold it in the shaft.
How are the brass nozzles removed for inspection of check valve balls and springs, heat on pump body and twist the fitting?
No, don't twist.
Scribe a nipple heading line on the pump, clamp the fitting by the top in a vice and make a aluminum punch to tap the pump off the fitting.
Be careful not to lose the spring and ball. (Use EC Yamaha kit and will come with a new oem spring)
Keep track of the fitting and install back in the same location.
Clean well, then use a drop of green loctite #620 or hi temp #640 (hi temp not needed but can be used) then line up scribe marks and tap in with a small steel hammer until seated.
Chuck
Ahh, so... Thank you very much!
Do you measure the piston spring for spec length, or does the oil output tell the tale?
Sorry, not understanding what your referring to...
The check valve springs that hold the one way ball valves?
C
ok... turns out there is no leak. It was the oil feed hose out of round. The hose is so old it is no longer pliable and wouldnt form a tight seal allowing oil to seep past.
However... there are still air bubbles in one of the lines that show up each pump so I have ordered a rebuild kit from economy cycle.
Quote from: SUPERTUNE on March 09, 2020, 10:18:40 PM
Sorry, not understanding what your referring to...
The check valve springs that hold the one way ball valves?
C
No, the one spring in the upper part of pump that returns the plunger to lower detents on distributor shaft cam.
Sorry, no diagram available to me on this iPad. It's #10 on exploded view if you have that.
If you're having issues with old hoses I would replace with new. I've seen the hoses from the pump fail, and on my bike a few years ago I had the main supply line from the oil tank spontaneously split lengthwise from age and spit oil on my rear tire.
OEM hose is still available from Yamaha. (These are black hose BTW).
Oil lines going from the pump to the carbs, 2 required. About $5 ea. After trimming to fit you will have some left over because each part is 27.5" long.
90445-05M07-00
Also a good idea to replace the small metal hose clips, 4 required. Economy has these.
90468-02033-00
Supply line going from oil tank to pump
90445-09122-00
When installing make sure that the fixed ring on the outside of the hose is closest to the tank. This is used to capture the spring and hold it in place.