kawsaki punsun v -twin gpz 900

thundercougarfalconbird · Sat Jun 21, 2008 2:07 am

Post by **Fiddler** » Sat Jun 21, 2008 12:13 pm

The links work fine mate. try the advice at the top of this section and they can be put on display as thumbnail pictures. Being a complete luddite I found this daunting at first, but its quite liberating when you get it sussed and can use the computer more as a tool.

Love the build

I'm not overly familiar with Harley transmissions but I assume thats what it is? I havnt heard any feedback from people who have gone this route but it should prove a good match.
Keep us up to date.

thundercougarfalconbird · Sat Jun 21, 2008 3:49 pm

The transmission is a harley copy and it is a 6 speed box with 3" belt drive, i am not concerned with the punsun starter since i will be using the harley starter. the punsun oil cooler will also be tossed in the junk bin, it will be fitted with something much larger infront of the engine for extra capacity. lots of theings to consider , somtimes its good to stop and take a look at it for a while.

Curtis in Texas · Post by **Curtis in Texas** » Sat Jun 21, 2008 7:21 pm

One of the biggest concerns I've run into over the years of converting gasoline powered vehicles to Diesel engines has been the transmissions used behind gas engines are not buiilt as robust as the diesel transmissions. Seems the diesel power pulses are too intense for the small gears. But, I like the Harley Transmissions because they are made to handle some really strong odd ball power pulses from the Harley Motors.
So you ought to be good there. Will probably not EVER have a transmission problem with that set up. Cool build.

Interesting build. I have a round tubing bender that would make a really nice set of lower frame bars. Too bad we're so far apart.

Consider me subcribed to your build.

My parts gathering speed.

Curtis

Post by **Stuart** » Sat Jun 21, 2008 10:10 pm

thundercougarfalconbird,
Harley gearboxes are considered to be ideal for Diesel Bike projects but the cost is always a stumbling block. Could you tell us a little more about this copy box you're using? Like who makes them and if they are significantly cheaper than the real deal? It would be interesting to know

Stuart

roverthetop · Post by **roverthetop** » Mon Jun 23, 2008 6:08 pm

i am working on 2 "harley" builds as well. 6 speed "ULTIMA" gearbox. $600 USD, so it worked out in cost to my comet 94c cvt setup especially after jackshaft, bearings, final and gears for the cvt. i'd say its about a wash pricewise, as the ultima 6 spd doesnt need alot of secondary equipment. fabricating an inner primary to bolt the "harley" primary cover to is my next step. ebay US ultima 6 spd. they come in right side or left side drives, various finishes.

thundercougarfalconbird · Tue Jun 24, 2008 12:38 am

i ended up buying the trik shift trans with primary kit,it came with starter too, its looking like it will work out well. i do have to figure out what sprocket to get since it came with a belt pulley for the final drive, have to see whats available for 530 chain to fit the gpz rear sprocket. im not a specialist with harley stuff but im sure it will get sorted.

thundercougarfalconbird · Tue Jun 24, 2008 6:57 pm

this is the guys web store, he has a few different trans and primary drive systems

i hope the link works

http://cgi.ebay.com/ebaymotors/TRIK-SHI ... QQtcZphoto

Post by **Crazymanneil** » Thu Jun 26, 2008 4:58 pm

Interesting build you got going there.

I am also going the HD gearbox route. I thought about it for a while and considered the alternatives. I was wondering what bikes there were out there with separate gearboxes and then I thought about the harley. I was pleased to see that the EDIMO project had already used the Harley box so I knew it was possible (and co-incidentally the same engine as I am using).

After more consideration I went for chain primary drive, mostly because I think it will be less fussy about alignment although a good belt drive would probably take that out of the equation too. I was also able to get a complete chain primary off ebay from a guy in England who swapped his out for a primary belt drive too so that was a big factor.

So at the moment I have a 6 speed Ultima gearbox (black and chrome) left side drive, harley chain primary and clutch and harley chain primary case (which I was delighted to find should fit my application thereby meaning no need to make a one off chain case!). I'm glad I've gone this route so far as the harley box is reassuringly heavy. It was not too expensive either when bought through Demons Cycle on ebay but was gutted when I got hit up for £80 import duties. (russa frussa)

One of the nice things about the chain primary is the front sprocket has a spring and ramp setup that takes some of the pulses out of the drive, although that will hopefully be less of an issue with my 3 cylinder engine.

Anyway. My big stumbling block at the moment is to get a shaft between the engine output and the primary front sprocket. There is only 1 company in Northern Ireland that can make a shaft with splines and they reckon on it costing me around £350 (for splines at one end and flange at the other).

Another option I was investigating was to get the crankshaft output shaft off a harley as I believe these screw into the original flywheel. If I could get that sorted then I'd just need an adaptor and I'd be suckin diesel. The trick is to know which shaft I want when I don't know the in's and outs of all the harleys ever made...

Also anyone know somewhere in the UK that would sell me the harley shaft? I tried the dealers over here though they were not that helpful. They only knew of the complete bottom end for sale which was a tad expensive.

I'd be interested to see what you end up with for the final drive sprocket as I've not got that far myself yet.

Neil

pietenpol2002 · Post by **pietenpol2002** » Thu Jun 26, 2008 8:13 pm

Neil,

Could you weld a flange to one of the options below?

http://tinyurl.com/5auxtz

http://tinyurl.com/5csp9d

Ron

Post by **Crazymanneil** » Thu Jun 26, 2008 10:08 pm

I like where you are going with that although I don't think it will work for my application. Ideally I want to go Engine -> Flange -> Shaft -> seal -> bearing -> sprocket. If I welded to the shaft then I would not be able to get the shaft through the bearing for assembly. I do have that output shaft (standard one) sitting here though so its still tempting.

I'm looking at replacing the compensator sprocket entirely now and thus doing away with the splines to replace them with some other sort of fixing. We'll see what happens.

Neil

thundercougarfalconbird · Fri Jun 27, 2008 1:11 am

the belt drive system that came with my system uses a hub that bolts into the engine pulley, since it has a spline in it i cant use it but have to machine up a new hub with 1" bore and key.
Has anyone noticed the 1" crank shaft and 6 mm key? the 6 hp 10 hp and the 22 hp all have 1" shaft and 6 mm key, oh and a metric threaded hole , it is a good thing the bolthing flange is iso.

thundercougarfalconbird · Tue Jan 06, 2009 3:54 am

hi everyone, been a long time. i hope everyone had a good x-mas and happy new year, i have a a couple pix little bit of progress since it got cold out. all the little things take soooooooo much time.

cumorglas · Post by **cumorglas** » Sun Sep 06, 2009 6:03 am

thundercougarfalconbird wrote:the belt drive system that came with my system uses a hub that bolts into the engine pulley, since it has a spline in it i cant use it but have to machine up a new hub with 1" bore and key.
Has anyone noticed the 1" crank shaft and 6 mm key? the 6 hp 10 hp and the 22 hp all have 1" shaft and 6 mm key, oh and a metric threaded hole , it is a good thing the bolthing flange is iso.

i am in just about the same position here. i am thinking my solution is 1" collar for 1/4 broach and then 6mm broach and appropriate shim. is this what you did? or is there a better solution? i'll have to buy the collar and broach as my little brother doesn't have them in his kit.

thundercougarfalconbird · Tue Sep 08, 2009 6:38 pm

unfortunatly when building you have to purchase tools to make what you want.
the 6mm broach is not terribly expensive, and im sure it will be used for other projects since all of these chinese engines have 6mm keys.

cumorglas · Post by **cumorglas** » Thu Sep 10, 2009 2:53 am

thundercougarfalconbird wrote:unfortunatly when building you have to purchase tools to make what you want.
the 6mm broach is not terribly expensive, and im sure it will be used for other projects since all of these chinese engines have 6mm keys.

that's what i was thinking too. i'm sure it's not the last time i'll use it. i found a set of collared bushings for fifteen bucks on ebay and there is a machine tool manufacturer in town that sells whole kits of broaches on an industrial scale but i just discovered will let me buy seconds for a little more than scrap. even if i don't find a 6mm in the seconds pile a brand spanking new one is only thirty bucks with shims.

it is really frustrating at times looking at shelves and shelves of tooling and not having the one bit or piece you need. the frustration is occasionally balanced by suddenly discovering that some piece you took in auction as a part of a lot to get one piece is now the piece you need.

DieselBike.net

kawsaki punsun v -twin gpz 900

kawsaki punsun v -twin gpz 900

transmission

drive systems

trik shift trans

sprockets and hubs

cold weather makes for some time to work on the bike project

Re: sprockets and hubs

Re: kawsaki punsun v -twin gpz 900

Re: kawsaki punsun v -twin gpz 900