yamaha lc 350 cases

[preben54]

hi all, will rd 400 gearbox and clucth work in early lc 350 cases and I what about cranks , I checked tz 750 cyl will fit on studs , thx

[m in sc]

yes on the transmissions far as i know, the cranks, you can't fit a 400 one in there but the lc ones are easy to find in europe new aftermarket.  I know, i bought one and fit it to an ac motor. can you put a 350 ac crank in there, im 99% sure yes

[preben54]

thanks Mark

[Jspooner]

yes on the transmissions far as i know, the cranks, you can't fit a 400 one in there but the lc ones are easy to find in europe new aftermarket.  I know, i bought one and fit it to an ac motor. can you put a 350 ac crank in there, im 99% sure yes

I would not be so sure about a 400 trans fitting the LC cases, something tells me it won't. I'm pretty sure the LC350 and RD400 trans are the same ratio though if that's what you are after. As for a crank, I bought mine from PJME in the UK. I would not bet on a 400 crank fitting the LC cases without major mods.

[m in sc]

400 crank won't work in an lc
 case.

[stresa]

RD400 crank webs are too big in diameter to fit into LC cases. As @Jspooner and @m in sc wrote, LC cranks are easy available in Europe. A RD400 transmission fit into a LC case but you need the RD shift forks and the cam shift. Clutch is the same anyway. An ac RD250/350 fits physically into the LC case but lacks length on the primary side to run the waterpump. And on the ignition side gas a different crank taper for the ignition rotor. So, a RD250/350 is no option also or needs a lot of modifications.
Regards Uwe

[m in sc]

if i were to build a motor on lc cases id def go w an lc crank. however.. those tz cyls also fit ac cases.. and also.. 400 cases if you want to do a stroker motor. this will of course require some rod and piston swapping,  of which I don't know the details. but the ac cases can support an lc topend w a 400 crank for sure w an elec water punp. just depends how weird you  want to get. 

[stresa]

Mark,
you are right that a TZ cylinder will fit an ac or TZ case. I have an ac engine with TZ cylinder and TZ waterpump and like you an ac engine with LC cylinders. I think you run this engine with a electric waterpump, mine has again a TZ one. A LC or TZ cylinder fit a RD400 case but will not function proper with a RD400 crank. It will not run properly if at all. Equal what you try you will not get the right timing. Often tried but never achieved.
Regards Uwe

[m in sc]

i think you have to jack the cyls and do a bit of rod swapping and a different length piston to make it work. IMHO def not worth it.  Im not 100% sure on this actually ever being done though. I thought some pf the fahron stuff was done this way in the 80s. 

Ive done a few lc/ac BTW, the white rd indeed has a TZ pump as well.. 2004 or so. the old blue one had an elec pump as did another one i assisted with. i have enough to do another down the road. maybe.   

[preben54]

Thx guys, I have 400 cases with tz crank and tz cyl and waterpump on it now,in a 1976 tz monoshock frame , I was thinking of LC cases and like you all say aLC crank any one have a lc trans for sale ,this way I could run a oilpump thx againPreben54

[SoCal250]

*Off Topic*
Hey Preben, early this week while out on a ride, I noticed the SUV sitting in front of me at a red light had a personalized California license plate that read 'PREBEN'. I thought of you and wanted to get a photo but the light changed too quickly for me to get to my phone. And it had a Denmark license plate frame with Danish flags.

OK, back the regular program...

[stresa]

Mark,
the Fahron watercooled RD400 cylinder and head were castings done by Fahron(Ron Philips). Around 16-20 kits were built. Even he doesn't know it exactly. I spoke with him at a bike show about this kit over 20 years ago. I asked him if he could do the kits again, he answered he can't do it as he didn't know where the castings are....... One of the very few aftermarket part I never had/still have. Sourced 2 times a kit for sale but both times someone other was faster or had a bigger wallet. He told me that he done the kit as it was not possible to put a TZ cylinder on a RD400 case with 400 crank. At least not that it run properly. These are my 2 watercooled as engines. I have another one with electric pump solution I used in the 80tees somewhere in a box.




Regards Uwe

[m in sc]

ah. that explains it . i wasn't sure, obviously

[Jspooner]

Thx guys, I have 400 cases with tz crank and tz cyl and waterpump on it now,in a 1976 tz monoshock frame , I was thinking of LC cases and like you all say aLC crank any one have a lc trans for sale ,this way I could run a oilpump thx againPreben54

I think I should have an LC trans I could sell.