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f7 F7 Restore--New Member

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This is my first post since it is my first dirt bike project.  Last winter I acquired a 1972 Kawasaki 175 F7.  It is a non-titled, and was a non-runner when I purchased it last spring.  It is in rough "barn" shape but it appears everything is there.  The tank has no dents but the rust inside makes up for it.  I'm not sure that can be salvaged. The only work I had done to this point was an ultrasonic cleaning of the carb and to begin cleaning the tank with nails and "the Works".

zMqA5k1.jpg

Yesterday I worked with a friend to clear the air passage, we cleaned the carb using an ultrasonic cleaner.  Following an inspection of the wires we connected a battery.  With that and new plugs we had spark.  The bike fired up after a few kicks but the throttle stuck wide open so we immediately shut it down.  My previous experience has been on my KZ 650 so I know very little about these old dirt bikes.  I've got moderate mechanical skills having worked on the KZ with some great help from a model specific forum.  I'm hoping this site can be that source for this bike. Some initial questions are listed below.

1. If anyone has one of these I could use a photo of the top of the carb when it is installed.  Based on the acceleration being stuck it seems as if a PO may have reversed the two cables coming into the carb.  I had not removed the top of the carb when I took it off.  I suspect this because the cables twist around one another when the carb is installed with all notches in the correct place.  I'm referring to the two throttle cables seen at the top of the carb here.  Are they inverted?  I have not tested the threads yet to see if that is even possible.

JLcY1lc.jpg

2. I'm not absolutely certain based on the short run we did if the oil pump is working.  We ran some mix to be safe.

3.  I'm not above very specific instructions on the oil requirements on this bike.  There is an oil fill cap on the crankcase and the oil tank itself.  I'll do some more reading in the Clymer manual I have but it seems as if oil will be required in both areas.

Anything else about the F7 that folks know will be helpful.  It looks like an active forum so I am optimistic.

Corey

Edited by Stosho
added a photo
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Sorry to reply to my own thread but a friend of mine seemed to solve the riddle of those cables mentioned in item number one.  Based on the relationship between that cable and the notch on the cap in the link below it seems mine were inverted.  This is likely the reason this bike has not run in years.  

https://www.ebay.com/itm/Kawasaki-NOS-NEW-16001-197-Carburetor-Assy-F7-Enduro-175E-1971-75/361414984517?epid=1611866218&hash=item5426030345:g:JEoAAOSwA4dWKisg&vxp=mtr here

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It is sorted out.  We were able get the notch on the cover lined up correctly by reversing the placement of the two cables.  This reversal must have frustrated the PO and could be the source of such an aged bike with so few miles.

kKUv1PN.jpg

When we install a NOS stock throttle rod which I was amazed to find on the auction site the carb should be set.

4wi8imR.jpg

The oil line seems to be functioning but I am still mystified by whether or not oil is required in the crankcase.  The manual says it is not required in the rotary valve because oil would splash up and foul the plug.  If that is the case why is there an oil fill cap on the crankcase?

Gi7ptlB.jpg

HK7HjXw.jpg

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The oil tank gets filled with two cycle oil that is suited for automatic injection. The pump meters oil to the engine based upon throttle position and engine RPM. If you are unsure the oil pump is working, use pre-mix to get the bike running.

The oil cap on what appears to be the "crankcase" is for transmission lubricant. ATF, Rotella and dedicated motorcycle gear lubes are popular choices.

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19 minutes ago, DaveCR said:

The oil tank gets filled with two cycle oil that is suited for automatic injection. The pump meters oil to the engine based upon throttle position and engine RPM. If you are unsure the oil pump is working, use pre-mix to get the bike running.

The oil cap on what appears to be the "crankcase" is for transmission lubricant. ATF, Rotella and dedicated motorcycle gear lubes are popular choices.

Thanks for the response.  We did use pre-mix as you described and it worked well to fire the motor.  As I understand the second part of your response that transmission lubricant must simply go to the clutch and not into the crankcase.  Is that accurate?

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17 hours ago, Stosho said:

It is sorted out.  We were able get the notch on the cover lined up correctly by reversing the placement of the two cables.  This reversal must have frustrated the PO and could be the source of such an aged bike with so few miles.

kKUv1PN.jpg

When we install a NOS stock throttle rod which I was amazed to find on the auction site the carb should be set.

4wi8imR.jpg

The oil line seems to be functioning but I am still mystified by whether or not oil is required in the crankcase.  The manual says it is not required in the rotary valve because oil would splash up and foul the plug.  If that is the case why is there an oil fill cap on the crankcase?

Gi7ptlB.jpg

HK7HjXw.jpg

To clarify, the gearbox and clutch are lubricated from 4 stroke oil or atf that is poured directly into the crankcase oil cap. It is separate from the rest of the engine.

The oil pump and plastic oil reservoir uses 2 stroke oil to lubricate what is seen in the above sketch. As DaveCR said, if in doubt whether this system is working, go with premix in your fuel. But! Some of these older 2 stroke bikes had to have a functioning injection system to ensure oil was getting to the main bearings. About a half dozen paragraphs into the attached link seems to confirm your F7 is one of these. http://articles.superhunky.com/4/133

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Thanks for the outstanding response.  I've not run the bike for an extended period for obvious reasons, the throttle was stuck open.  With the repairs made I can idle it this weekend.  It appears that oil has made its way from the tank into the oil pump.  The cable on the pump is intact and moves with the throttle as expected.  Beyond that I don't know how to tell if it is running properly.  I'll watch it as I work the throttle.  If there is anything else I can do to assure it is working properly please share.  I'll update this after the work tomorrow.

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When you start the bike, lift up on the oil pump cable, simulating full throttle operation, and let the bike idle. If the pump is working the engine will soon begin to smoke heavily from the exhaust.If your oil line from the pump to the engine is translucent you will be able to check for any air in the line at the same time..

 

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Thanks for the responses.  I was able to get the carb sorted out mechanically with the new throttle rod and rotating the cables.  The bike started up and I had an idle for some time.  It seems I could have some problems with air leaks.  Once I secured the carb in with the cover and boot the idle was better but I am still having some challenges with high RPMs.  From research in other posts it is very possible some of the gaskets are dried and creating some air leaks.  I'm open to any input on that point if you have any.

I now know it will run.  From here I'll need to develop a project map of sorts to get it trail worthy again.  Work will need to start with installing the correct battery, setting points, tuning the carb, and replacing the cables.  Advice on next steps is always welcome.

Other Sources of information for reference:

http://www.kawasakimotorcycle.org/forum/vintage-motorcyle-info/157577-f7-wont-idle.html

http://www.kawasakimotorcycle.org/forum/vintage-motorcyle-info/148468-1971-f7-175-fuel-vacuum-oil-lines.html

http://www.kawasakimotorcycle.org/forum/vintage-motorcyle-info/110368-whats-my-problem-engine-bogging.html

 

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6 minutes ago, S.O.A.N.Z said:

what gaskets are you after ?

I'm not exactly sure.  Based on some of the information I am seeing it sounds like I could run into problems related to air leaks in the crank case seals during the restoration. It is a preliminary thought based only on the fact that in the little bit of time I've had the bike running high, even dangerous idling seems to be a problem.  I'll need to get into the project deeper before I go to that more extreme measure.  I've got some low hanging fruit to start with.

Do you have some F7 items available?

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23 minutes ago, S.O.A.N.Z said:

no - but im good at finding obsolete parts - cross-referencing that sort of thing

Great to know.  My first search will likely be for some throttle cables.  The casing on mine are cracked and brittle.  I'll take a good look at them but I don't know that they can serve much longer.

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2 hours ago, S.O.A.N.Z said:

is this going to be a full restoration project ?

 

I'm not sure yet but I doubt it.  I do not have a title. I want to get it running as well as possible and see where the bike is at then.  I would like to have it in condition to run it in some vintage enduro or endurance events.  Absolute originality is not a priority if there are upgrades to performance that will not clearly change the aesthetics of the vintage bike.

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I purchased a 1973 tank hoping it would fit my '72.  Seems to be a near miss.  The center space is a bit narrow to host the wiring harness comfortably and the mounts don't seem to drop quite far enough.  If anyone has a source that indicates which years cross reference that would be helpful.  If there are any hillbilly engineering ideas to get this to function as a back-up I'm interested in that as a short term yet functional option while I work to remove the rust from the old tank or find a suitable replacement.

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what color was the tank you bought ?

can you take a pic of the underside of it ? - and also your tank

Edited by S.O.A.N.Z

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In both of the photos below the new tank is on the left and the original is on the right.  The new tank seems to be about 1/4" to narrow. The original tank looks decent her but it has lots of rust inside.  I'll continue to try and save it but I am not all that optimistic.

i7QJlER.jpg

egPedxi.jpg

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