Does XJ 750 gaskets fit to Maxim 700 N?

Hi from Finland!

We have had Yamaha Maxim 700 N -86 now about an year. Everything has otherwise ok but we stupids bought it on winter when here was icy roads and about 30cm snow so we couldn´t test it well.

On spring when get to ride first time we have some problems with carbs, when motor gets warm it runs about 4000rpm "idle" on itself :lol: fixed that with synchronization. Second problem was poor startup. Like in this today filmed video but when bike was outdoors it was 5 times worse. That continued trought summer.

Now in winter bike got indoors and service started. First we measured compression pressures and it told bad news. 1 and 3 cylinder didn´t have pressures on cold at all, and with warm engine under 6 bar. Today we measured valve clearances (last time on summer, were ok) all the inlet valve clearances where under 0mm! So we think it is time take cylinder head off.

So the question. In europe (or only in Finland) it is really hard get gaskets, especially head gasket, which btw costs 100€ . In ebay I found XJ 750 81-84 gasket set. I look specs, bore is same but does those gaskets fit to 700 Maxim? Especially cylinder head gasket.

In my eyes there is only those two extra routes on bottom :lol: So might fit when cut those extra things away?


ps. Thank you for replays in advantage and sorry for my bad english.

 

Welcome to the site !!

I think you can make the 750 gasket work on your 700 even if it's not a perfect match.
You can also get one from our parts man - info@XJ4EVER.com - on this site.

From your video, I'm guessing your Pilot (idle air - fuel) system is not completely clean.

Search this site for - "church of clean"
Your English is not bad at all !

 

Although the bores are the same between the 700 and 750cc air engines, the head gakets are not. It may be just those two extra passages, but it may be due to the thickness and/or compressibility of the gasket material itself.