440 Kit

thanks Hick

l'm self taught & i had no website & i was 19.

you've got a website & some people to help you. you can buy a tuning book & read it, & read it, & read it again. the squish(quench) you can do.

if you crack cases it will be because Yam made them for what it is meant to be. i'm telling you, you have no idea how many (roadracing) sets of cases the top boys get through on a suspect model. u-n-b-e-l-i-e-v-a-b-l-e!

at the TT you take a Duke & 3 sets plus you've fitted a new set before you go!

singles-don't take em over 8K or it's £1,000 plus VA tax at 17 1/2%. the top boys are sponsored, they get it free, or they pay trade, they don't pay VAT.

you don't have to stick your head in the noose.

tell us how you broke your cases please Hick?


Originally posted by Taffy:

thanks Hick

tell us how you broke your cases please Hick?


Not sure, but it looks like:

1) several teeth on 4th wheel and pinion gear chunked off

2) then collar/dogs on 3rd pinion gear, where 1st shift fork rides, broke

3) then fork got in a bind with broken 3rd pinion gear and broke the case where the fork shaft rides

4) then the fork got tangled in the crank and gouged and bent it. But it didn’t stay there and the bike was running (I pulled in the clutch when the tranny did lock up) until I killed it (I was already hysterically mashing on the kill button before I came to a complete stop).

I was going pretty hard and had just upshifted into fourth when it happened. All I felt was a little hesitation/false neutral sensation when I shifted, I clutched/let off the gas and CLUNK.

Wouldn’t you know it this was the ONLY ride I’ve ever been on w/out a phone. So, in order to prevent long walks in the desert, always carry your phone (even if it doesn’t work), your bike is sure to break otherwise as my experience has proven.

Anyone who reads this that has R&Red a crank from a case half I would appreciate some pointers. As I mentioned, the local motorcycle brain trust advised I use a hammer :)

Hopefully the “bearings in freezer” trick will suffice…

Hick - The crank needs to be pressed, or you need to buy the Yamaha tool listed in the manual. Heating/cooling and force won't cut it.

Taffy - I've yet to see a 94mm piston hurt the small end bearing on any '98 or '99. Maybe you've seen more of them than I have. Care to share some specifics?

my point is that it is very expensive to bore & stroke the engine & they shouldn't do it until they've done the simpler stuff first,

The bore is cheaper than a pipe and is far more effective.

The bore and stroke setup is a really BAD idea IMHO, so you'll get NO arguement from me.

i still question the reliability & will do for another year. of course we need someone to be the guinea pig & you just got the job.

There isn't enough data on the 97mm setup to know how reliable it will be over the long haul. Time will tell. There is no doubt in my mind that a plated 94mm (420) kit is just as reliable as the OEM 92mm setup.

i was going to respond to your comments on the cam timing & then i realised that you've changed some of my previous comments. that i won't put up with.

I'm VERY careful about quoting people correctly (hence the use of the quote function) , so you're going to have to help me out here and tell me what the hell you're talking about :)

Originally posted by Rich Rohrich:

Hick - The crank needs to be pressed, or you need to buy the Yamaha tool listed in the manual. Heating/cooling and force won't cut it.

Thanks Rich, I suspected as much. The PNs (there are 4) in the manual for the crank installing tool, I was told (North County Yamaha) totaled $450 :)

That is out of the question for a tool I’ll (hopefully) be using only once. That’s more $$ than the crank! I was thinking of fabricating something out of a steering wheel puller and a few long bolts, based on the picture in the manual. Any thoughts?

I got a mechanic from NCY on the line and he was the one who suggested heating and cooling the crank/bearing/case to get it in the left case half. He said they didn’t use any special tools to install cranks in a case. Everyone I’ve asked has given me a different answer, so far I’d rate your’s as the most credible (“just use a hammer” would be the least credible).

Thanks again for the advice.

It shouldn't be too difficult to fabricate something similar to the Yamaha tool to install it, at which point the heat/cool method will be helpful. It takes some serious squeek to get it OUT, so all I can suggest is be VERY careful.

OK Rich,

the 99 or 98 model or whatever was taken out to 94mm by some folk & they knocked the little end eye oval-it wasn't big enough & so for last years model they took the little end dia up 1mm. everyone had to pull their piston kits off the market.

you should know that when the japs make the smallest of changes to the power output EVERYTHING gets changed. they make everything out of the cheapest material they can get away with & also make it only just strong enough.

i disagree 200% about the cam timing. it most certainly is generic & it's the pipe that should complement the cam & not the other way round.

what do you think these things are? the leading edge of technology? a 1000cc duke puts out about 170bhp-that's 85bhp per 500cc & were on about what 50+bhp for 400cc.

as my initial notes point out (more ummpphh!!), there is an AREA in which the cam timing should operate. when yamaha set the timing outside this as a fudge you are in a no lose situation. i've found a moderately large increase in performance by simply shifting the timing into this area.

it could be improved even more-but i'm happy & have made it clear to everyone that i'm no longer prepared to spend countless hours on the bike. i did that as a young man. i've found an increase, go get it.

in a previous post, which i can't find, i stated that you could pull the camwheels off & press them back on in exactly the right place as long as you weren't experimenting but were happy to take my figures. i find once off & once on again to be a perfectly acceptable risk.

you ask yamaha why they make hollow cams & why falicon make a statement with every set of camwheels that they NEVER have failures-why don't you argue the toss with them not me!!!!! so that's Yamaha & Falicon that are wrong. UMMMMMM!!!!

i'm afraid you've got so much technology going on rich, your head is halfway up your air filter.

the equipment i used to do the job, as descibed before, was,

strip of metal from barrel base screw & twisted to vertical

strip of metal twisted all ways up to hold dial guage

old rivet head to fit in dial guage & sit on cam bucket

dial guage(£25/$40)


i already owned the last two.

i've done all the figures & got it right first time. that took years to learn & balls the size of tennis balls to do.

the next man who tries will know like those following edmund hillary (getting a bit dramatic this!!!) that it can be done.

rich, i'm glad we agree about the bore/STROKE thingy-that's important.

you don't need telling this do you rich, but 2mm on the =don't touch the head. 5mm on the (original) bore squish must be modified to a two-stage squish or the bike won't rev.

this bike revs, if i may paraphrase clarke 'the 13.5 & 420 piston doesn't spin up the same'.


i believe with the brits having less money that we have more home tuners than you. i know ten men within ten miles of me who would help me check my cam timing. i live in the Fens in a village. find an ex-roadracer they'll help. most of them would love it.

best regards to everyone

i know i had a pop at uncle sam & was only trying to winde you all up. i didn't succeed did i!!!! fun this innit!!!


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