Driveline 421 Big Bore Assassin top end kit

[Deleted]

Hi All

Does anyone have any info/experience with this kit, good bad or indifferent, I know JS about them or big bore motors

68mm nikasil bores, port spec 196 exhaust, 124 transfer durations, no baseplate required designed for use with 4mm stroker crank and 115 rods

So I get the cranks size ok and the bore size ok however the port figures leave me standing, no idea what they mean

I have a chance at buying a brand new unused whole ? top end locally to me, they guy has a Banshee, I don't know as yet of it comes with pistons and a head, however i can get it at a good price going by what they are new, I'm told they are tuned for mid to high range

I have a set of keihins bought off Andy748 here, not sure if they are 26's off the top off my head, and I do have some 28 Mikunis, seller has some keihin 33's to sell too

So could anyone decipher this info for me and are they suitable to put on a currently stock LC2, not necessarily looking for a project however the stories of 421's have pricked my attention

Any advice would be very much appreciated, I'm not after 100BHP just something good enough to ride on the street for a bit of fun

Should i get for posterity or jump in with both feet


Thank you


Howard

[muttsnuts]

HI Howard,

I have built a few of these, there are 2 types of Assassin barrels, mid range and high bhp, the port timing determines the characteristics of the barrels, and of course the exhausts made to suit

To date I've used some 28mm and some 32mm carbs with them, with good results, I've managed to get the mid range ones to do high 70's low 80's, Russpuss's "shocker" in the build page has an assassin engine in it that I built for him, that's doing around 77bhp and 46ft/lb of torque at 8700rpm, so they aren't crank killers and a good road barrel

I'd class them as a better option than the Athena barrels (Similar price point) but not as good as the cpi serval barrels, but then they are more money.

Of course you can mix and match the various components to give different results in power and torque, so cylinder head style/CC's etc, pipes, ignition, carbs, reeds etc all have a bearing on the final outcome

HTH

[Tobyjugs]

Hi Howard I have an assassin 443 top end in the Bakker project at the moment. I've done some runs and it looks very promising. I can't give a thorough assessment , as the clutch is not man enough for the engine. My engine was kicking out 72bhp and 55FT/lb.

The Assassin Wiseco pistons which come with the set have slightly different windows in the piston skirt compared to other 68mm Wiseco pistons.

Oh yes jump in with both feet.

[Deleted]

Hi Guys

Thank you for the feedback, very useful

I'll go and have a squiz, at 300 quid they seem like a good buy, if its the full top end

Howard

[Deleted]

update

got sent pictures, it seems they have been used but not by him

scorch marks on the top of the pistons gave it away, domes are included unsure of the size though

so not new which changes the equation slightly

Hmm

[Tobyjugs]

If the pistons still have the piston rings vidually check the end of the rings as this is where the rings wear the most. This might be able to give you an idea of how much use the partd has had.

[Deleted]

From a suggestion from JonW I'm going to email Driveline to see what I should expect to see

I'm thinking the guy has had these for sale a few years back as bits of his ad are for some reason ringing a bell

I don't really think he knows what he has, judging by some of the answers to questions I've received, I doubt if he actually knows if it is a LP or HP set

There is also no head with it, so as second hand aren't worth the 300 he wants for them, from what i can see the only thing new is the throttle cable and the base gasket

Once I get the info back from Driveline I'll go armed with more info and go from there

Appreciate all the feedback

[jon]

I fear that this aftermarket banshee cylinder route may be the only viable option for YPVS engines in the future.

I’ve been looking at the price of cylinders rise for years, as well as the supply dry up.

Plus there is the extra expense of the valves themselves.

Jon

[Deleted]

Update

So I emailed Driveline in the US who were supposed to have carried out the rebore Nikasil liner and porting

The barrels were supposed to have a 68H or 68L stamped under the intakes, no stamp was visible

The barrels look like they have been powder coated at some stage however the owner said that's how he got them, the barrels have 347cm3 stamped on them as you would expect from a banshee barrel

I have asked the owner for documentation that they are Assassin barrels and that Driveline did the work on the porting otherwise I'll have to pass on them

I've no idea what a Nikasil reline looks like, although I could still see honing cross hatching on the inside of the barrel, the ports were very smooth on the edges so it has been done pretty well

There were a couple of dark crescent shaped marks above the ports on both cylinders, it doesn't feel like a seize has happened as they were smooth, however i'm being cautious

I measured the bores and they were 68mm across in about 6 different directions, so didn't appear to be oval

I really don't know if they are just normal Banshee barrels bored out to 68mm, if this is the case then I doubt I'd get much life out of them

Any ideas?

[Tobyjugs]

Drive line come with 347cc on them as a sort of sleeper thing.

[JonW]

Athena also say 347.