79 YZ 400 Questions

wpark89
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wpark89
Edited Date/Time 8/5/2014 4:13pm
I decided to pull my grandfathers 79 YZ 400 out of the garage and clean it up a bit. I went to change the front tire and found several small cracks in the stock DID rim....I was curious if I could lace up something modern. I have several Excel and Pro Wheel rims laying around off KTM's and Suzuki's from the 90's and 00's and am hoping something will cross reference.

Wondering what model rims you guy's use for YZ restorations?

How much fork tube should stick up above the top triple clamp. I know some is normal on these bikes....but is there a correct height that works better that I want to set it at?

I want to put a Gunnar Gasser throttle on it...probably a Motion Pro....what cable do I need to use with the stock carb to hook up a newer throttle assembly?

Other than that I need to change the fork seals and I put a new air filter in it and it's basically ready to go. By simply grinding about 1.5 mm off my stock RMZ 450 pegs I was able to mount them right on the YZ....
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wpark89
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wpark89 8/4/2014 5:30am
8/4/2014 5:30am
One more thing. I dont want to spend a bunch of money updating the front end...but I really dont like how the handelbars mount back at such an angle. Can I use a 1980 250 or 465 top clamp? Are the forks the same size? It looks like the handelbars mount normal on top of the 80 models?
barkhard696
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barkhard696 8/4/2014 6:45am
8/4/2014 6:45am
I could be mistaken, but didn't the '79 YZ400 use a one-year only piston? I understand that these can be difficult to locate (or expensive),.. but as far as the clamps go, I'm positive I've seen these year 250s with the later 43mm fronts and DLS brakes.
PN27416
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PN27416 8/4/2014 7:50am
8/4/2014 7:50am
On the gasser from Motion Pro, just tell them what carb your hooking to. They'll know what cable you'll need, might even be on the web.
BigAl
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BigAl 8/4/2014 9:10am
8/4/2014 9:10am
wpark89 wrote:
One more thing. I dont want to spend a bunch of money updating the front end...but I really dont like how the handelbars mount back at...
One more thing. I dont want to spend a bunch of money updating the front end...but I really dont like how the handelbars mount back at such an angle. Can I use a 1980 250 or 465 top clamp? Are the forks the same size? It looks like the handelbars mount normal on top of the 80 models?
Can you use a different bend bar? Maybe something without so much sweep?

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wpark89
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wpark89 8/4/2014 9:17am
8/4/2014 9:17am Edited Date/Time 8/4/2014 9:18am
Id really like to get the bar mounts moved up on top the clamps so I can use some of the bars I already have. There are quite a few '80 250 and 465 clamps on ebay cheap if they will work on the '79..
lostboy819 8/4/2014 11:41am
8/4/2014 11:41am Edited Date/Time 8/4/2014 11:43am
I didn't feel old until I read " my grandfathers 79 YZ 400 out of the garage" I bought 2 new YZs back in 1979 and 78 and 76 Sad
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sandman768
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sandman768 8/4/2014 12:58pm
8/4/2014 12:58pm
i have a 79 yz400. 81 465 43 mm front end bolts right on, clamps and all, stock frnt wheel & spacers will still work. look at any old pho"s from that era, forks are way up in clamps, mine are raised 45 mm above top clamp. 79 is a stand alone yr for many parts! piston, crankshaft & many gears! very, very hard to come by! new wiesco pistons can be purchased from rick horvat 1-330-995-0245. not cheap, 200.00 & up. i put tall renthal jimmy button bend bars on mine, but still could be taller & more forward. Whatever you do, DONOT deal with a website "back in the day" the owner, don, is a crook! i sent him my crank for him to rebuild, never saw it again.... i had Ca dept of motor vehicles investigate him, the investigator called me & said he has numorous complaints & does not even have a shop, the investigator scared him into sending my crank back, but it was not my crank, nor was it for a 79 yz 400. hard lesson learned . I have some good engine parts for this bike if you needsomething let me know. Speed & Sport in Pa had alot of oem parts avail for this bike, good to deal with, not cheap! good luck!
barkhard696
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barkhard696 8/4/2014 6:13pm
8/4/2014 6:13pm
>Whatever you do, DONOT deal with a website "back in the day" the owner, don, is a crook! i sent him my crank for him to rebuild, never saw it again....

That SOB Mendenhall got you too? He ripped me off for many hundreds of dollars and two shocks in 2009 (including a rare period WP for one of my bikes I'd paid almost $400 for from eBay). I did get PayPal to partially refund some of the money I'd sent him for payment, which produced a flurry of threatening Emails from him, and abusive calls to my buddy who was helping me on the resto. Emails stopped when I reminded Mendenhall that he was free to take the issue up with me next time he was in Texas, just as I was the next time I went to a USC event in SoCal.

I'm flabbergasted that this guy is still around and pulling his scams... there's a whole section on Mark's Vintage Swapmeet website on his scams.

Apologies for the rant.
sandman768
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sandman768 8/4/2014 7:16pm
8/4/2014 7:16pm
sorry to hear that barkhard, hard to believe someone in our small community would pull that. I too went through pay pal & was able to recover all monies, but was still out a crankshaft, luckily I found a good ebay shaft for good price. I was an Insurance inspector for 20 yrs & been involed in many fraud scam investigations. I had a dmv inspector go to his business, which was really a condo and an old weak person scamming the vintage mx community. karma will prevail on this d/bag
gwilliams107
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gwilliams107 8/5/2014 3:02pm
8/5/2014 3:02pm
barkhard696 wrote:
>Whatever you do, DONOT deal with a website "back in the day" the owner, don, is a crook! i sent him my crank for him to...
>Whatever you do, DONOT deal with a website "back in the day" the owner, don, is a crook! i sent him my crank for him to rebuild, never saw it again....

That SOB Mendenhall got you too? He ripped me off for many hundreds of dollars and two shocks in 2009 (including a rare period WP for one of my bikes I'd paid almost $400 for from eBay). I did get PayPal to partially refund some of the money I'd sent him for payment, which produced a flurry of threatening Emails from him, and abusive calls to my buddy who was helping me on the resto. Emails stopped when I reminded Mendenhall that he was free to take the issue up with me next time he was in Texas, just as I was the next time I went to a USC event in SoCal.

I'm flabbergasted that this guy is still around and pulling his scams... there's a whole section on Mark's Vintage Swapmeet website on his scams.

Apologies for the rant.
That guy is due some bad mojo if there is any justice in this world!
He burned me on some work on my 79 YZ250 restoration also.
swatdoc
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swatdoc 8/5/2014 4:13pm
8/5/2014 4:13pm
Sure glad I read this post - I found that "back in the day" website and thought I had struck gold! Was probably gonna be ordering a lot of stuff for the 81 250 I'm getting.
Thanks guys!!!!!

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