crf/xr 80 engine help/advice

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blkwdw

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Need some advice from the people on here. I bought an xr 80 that whats in bits round easter time this year in a plain to get it to fix it up for my daughter to ride on. I also bought a crf 80 from the same bloke needing new plastics fro my wife to ride. I am only just getting the xr80(97model) now. I used the parts needed to get it running of the crf thinking i'd rather buy new parts for the crf i'm keeping and put the used parts on the xr i will now be selling.
I put the stator and flyhweel and carby of the crf on the xr and got it started. I did try starting it with the xr's carby but it wouldnt and kept overflowing. Well once started it makes a loud squeeling noise whilst running. Sound like from the bottom end. What would be causing this?
Also it wont change gears and is stuck in gear and the clutch doesnt disengage either.

Now if this is going to need major parts replaced to get it running i'm not sure i want to put the motor back in the xr. Can anyone tell me if i can replace the parts in the xr motor with new crf80 parts then put the new engine in the crf80 we are going to keep and put the current crf80 engine in the xr and sell it off. The crf engine is running fine so no work needed on it.

Also are the carbie identical?

I also have an xr 100 bottom end that had caught fire i got for free. It complete minus stator and the add ons. Are any parts they may be good internally interchangable.?

Heres the bike running
 
do you mean CRF70, instead of CRF80 ?
or a CR80 ?

it may have started to spin a bearing, and that's what is squealing ?
sounds like you may need to pull down a couple of engines and pick the best one to start with, then rebuild it from there
 
squealing could also be clutch issues too, it's very hard to diagnose over the net.

can you make a video or 2 of the noise and post them up here ?
 
its an 08 crf 80 an 97 xr 80 i have. Dont need to pull both engines apart as the one in the crf80 now is fine. no issues with it. What i'm keen to know is are both engines the same. If i have to rebuild the xr80 engine will new crf80 parts work? I'd rather the new engine in the bike were keeping. I have to pull it apart regardless to sort put the shifter problem. I have a video yes but photobucket is having trouble uploading it.
 
Pulled the clutch cover off. The plates were stuck together a bit but i'm not sure how stuck they have to be before they cause a problem or should they not be stuck at all. Cant tell if there worn or not, will give them a clean soak in fresh oil and reinstall. Now the gears shifting or lack of it. After pulling the clutch of and watching the gears while going up and down the shifter fork is not moving up to spin the sprocket thing. If i push it up with my hand it goes up and down gears fine. What part is missing or broken to make the fork like this?
 
Theres is no spring in the part that slides up and down. According to partzilla there is supposed to be. Also how many gears has a 97 model got i could only find 4 gears.
 
thats the crf80 not the 97 model xr80. if it only has 4 gears wats the problem there.
 
I'm not sure how the transmission works on bikes but even with the crf80 i could only find 4 gears. I know from riding it, it had 5 gears. If u push the selector all the way down it will only go up 3 more times. How is that if it has 5 gears?
 
You may find it needs to be running to select all five gears, my crf100 is very hard to find neutral, it helps to give it a little roll back.

Motorcycle trans simply put are gears which slide along one shaft to mesh the the appropiate gear on the other shaft. The gears are moved along the shaft by shift forks (picture in the diagram above). The shift forks are moved by the shift drum which is moved by the gear shift spindle which is rotated by the gear lever.
So what you are saying is that when you move the shift lever nothing happens? Does the spindle move at all? Pictures would help also.

Also do you mean it is missing the spring which is part no.11 in the diagram above? This spring allows the spindle to rotate back to its original position ready to select the next gear.
 
GooseMan said:
You may find it needs to be running to select all five gears, my crf100 is very hard to find neutral, it helps to give it a little roll back.

Motorcycle trans simply put are gears which slide along one shaft to mesh the the appropiate gear on the other shaft. The gears are moved along the shaft by shift forks (picture in the diagram above). The shift forks are moved by the shift drum which is moved by the gear shift spindle which is rotated by the gear lever.
So what you are saying is that when you move the shift lever nothing happens? Does the spindle move at all? Pictures would help also.

Also do you mean it is missing the spring which is part no.11 in the diagram above? This spring allows the spindle to rotate back to its original position ready to select the next gear.
Click to expand...

Yes it was missing the spring. I have got one put in now and t changes fine but just only going through the 4 gears but like said maybe it needs to be running to engage them all. Hoping soaking the clutch plates then reinstalling will fix the clutch not disengaging
 
The sqeeling is hard to know what it is unless you are a bike mechanic who sees this more often. I think my67xr is probably right with the bearing being loose but you would have to tear down and inspect all the parts. I wouldn't be swapping engines with the crf if I were you, the xr engine sounds like it has had a hard life and may have problems with it again later on. Just a though. Hope you sort it all out soon
 
GooseMan said:
The sqeeling is hard to know what it is unless you are a bike mechanic who sees this more often. I think my67xr is probably right with the bearing being loose but you would have to tear down and inspect all the parts. I wouldn't be swapping engines with the crf if I were you, the xr engine sounds like it has had a hard life and may have problems with it again later on. Just a though. Hope you sort it all out soon
Click to expand...

I was only going to swap it over if i had to rebuild the xr's engine. Figured better having a fressh engine in my daughters crf then in a bike i'm selling. hoping the squeel is the statot will get it all back together with a clean stator and see what happens.
 
Yes and no. I just put the crf carby on it. Will rebuild or replace the other carby with new one. Not sure how to set the float to stop the overflowing
 
if it isn't overflowing due to dirt etc being stuck in the needle and seat
then, to lower the float a bit, bend up the little tab on the brass section, in between the centre of the floats
just go a little at a time.

what carby? each has their own float height setting
 
I have cleaned the carby once but when i put it back on and turned fuel on it just poured out the over flow. The carbies are the same i think both have keihin written on them
 
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