250-500cc 1993WXC vs 1999 360WR

[juicypips]

2002 cylinder.

1993 cylinder its on 5mm squared graph paper hope its useful to some one.

 

[uranys]

Here is my best shot at showing the differences:

Looks like the exhaust port on the 93 is wider and not as tall. Unfortunately I don't know the first thing about port theory so I don't know how that affects things.

 

[uranys]

Here is the two scaled to about the same size and superimposed on top of each other

Looks like the exhaust ports are about the same height but flares out at the top and the transfers next to the exhaust port are a little wider at the bottom.

 

[Motosportz]

I had a 92 360 with dynoport pipe. Was all bottom end.

 

[msmith345]

Hmm, my 92 has a really strong bottom, but it really comes to life just before mid and carries on up into the revs. More willing than my 300 was to rev prior to the Lectron, though the 360 was slower to rev, it kept pulling. That's with the stock pipe, 38mm Lectron, and enlarged outlet on the intake boot.

I really should have done the rubbing on the ports, but I needed the bench space, and a backup bike, and put the 92 most of the way back together over the weekend. The engine had been sleeved by a previous owner, and it's possible they changed the port configuration.

 

[uranys]

I had a 92 360 with dynoport pipe. Was all bottom end.

That's a clean '92 right there!

I dunno if anyone is in the market for one, but I spied this one on cl in ohio the other day:

http://youngstown.craigslist.org/mcy/4360432576.html

 

[juicypips]

uranys your like the photo ninja, i can barley upload them correctly.
bike runs well untill i come off full throttle and then does the pulse thingy so the whole bike surges under you like its backfiring? does that make sence?
yup ive gotta re strobe it and since i took the decomp head off the 360 its a bugger to light an a little smokyer will lean out the lectron on the weekend see if this sorts the surge.

that 93 cylinder of mine was sleeved so as some one mentioned it could of been reworked.

 

[juicypips]

Here is a pic of two pipes

The gnarly is on the left and the fatty is on the right. They are pretty similar. I can't imagine there would be a big difference between them.

You still using the fatty? I cant go older than 2000 on fmf website so getting a new fat boys looking near impossible :,( wahhhhhaaaaaa
Cant get dynoport an giannelli are not producing anything older than 05
Dam looks like im gunna have to settle for gnarly or make one myself hints n tips pleae?

 

[justintendo]

why cant you get dynoport? they makes pipes for all liquid huskies...eighties up till 2000s or so..they arent the cheapest but they are very tough pipes and well made. im glad i picked the spark arrestor silencer model as its fairly quiet if you are easy on the throttle. has a great/strange exhaust note

my 95 is still the earlier style of 360, all around power band. with dp pipe it has good bottom and mid but has great upper rpm hit. its even better with the lectron. no choke hot or cold, 1-2 kicks almost everytime. to its credit, it started pretty damn well with the mikuni, but the lectron seems to do everything else much better.

 

[justintendo]

the Keilhin's an aftermarket add on isnt it?
toataly drew blank at looking for my port dimentions im slack i know, long days at work i blame.

must admit im looking for a little more poke up top im after the ideal poweralve setting at the moment mines set at the lower mid portion of adjustment, and the screws ontop of the valve cover? the ones that stop them falling into the cylinder.

p.s. looking for a new pipe but the gnarly seems the only one i can find available in uk and im after top not grunt the bikes got plenty of that.

have you figured out your powervalve? do you have the owners manual? theres a procedure where you adjust the max height open and the minimum height lowered.

 

[juicypips]

Yeh ive played with the valve i must be a rock ape as didnt notice much difference wherever i put it.
Will double check but thought they wouldnt ship may be being usless there.

 

[juicypips]

Emaild rich at dynoport so should get quote back inc shipping see if i have to remorgage my house

 

[uranys]

I'd like to hang on to the fatty, besides shipping it to you would cost a ton, You could probably make a 2000+ gnarly work, the mounts are the same but the stinger is a little longer but you could cut it down.

So i got hold of a '93 cylinder and put it on my 2000. It really does wake up the mid/top end quite a bit. I've been working on an '02 project bike for a while and i'd like to set it up the same way but I don't think it will be easy to find another '93 jug so I think i'll try to have a later cylinder modified to match the '93.

Here is a pic of the '93 and newer powervalves.

They are identical except the edges of the newer valves have been machined down to match the narrower ports so it should be possible to widen the exhaust port on a later cylinder and use the older powervalves

 

[2premo]

while they were side by side did you happen to measure the port dimensions and height from top
was planning to do this right away myself
did you notice how much easier it is to start

 

[uranys]

unfortunately i didn't but i'll do it when i tear the other motor down. I'd be willing to bet they are the same though.

As far as starting goes i just took off the decomp head and haven't gone on a ride so I can't comment on that yet.

 

[2premo]

pretty sure the porting changed on the newer ones just curious if the newer can be converted to the earlier
they do use the same head and piston so thats handy

 

[uranys]

i meant the port heights look to be the same. The exhaust port and transfers are narrower on the newer cylinders so yes, i'm pretty sure they can be opened up to match the earlier cylinders

 

[juicypips]

Right 2premo sink your hard white teeth into these cold facts!
1993 -2002 power valves side by side measured with digital calipers so as accurate as the lying device can be.

 

[juicypips]

Will measure exhaust ports transfer ports an any other bits i can after the cylinders have finished in the dish sorry partswasher

 

[juicypips]

Right ive measured these ports im stuck at how to measure around the cylinder as have no graph paper,
I have pictures of cylinders and ports too. View attachment 46130