DRZ Big Bore Kit

[Darran wrightMember]

Krusty wrote:

Quote:

Mate have a look at Thumper Talk.. http://www.thumpertalk.com/forum/forumdisplay.php?f=25

Pay attention to “Eddie Sisneros” he is the bloke everyone worships.. :laugh: :laugh: :laugh:

Heaps of information… You could spend a month reading.. :ohmy:

Get a bolt on.. Athena is the way to go from what I have read… 416 CC to 470 CC direct bolt on, done in a day no machining.. You will need to re-jet, cams etc.. Heaps forsale on ebay from USA..

Eddie Sisneros is the Guru when it comes to DRZ’s

[Darran wrightMember]

Trailboss wrote:

Quote:

Bana (an Old Bull) had a reliable banana, fitted a big bore kit, blew up twice hasn’t been reliable since. IMO any bigger bore kit unless the engine was designed for it will compromise reliability simple mechanical science and facts prove that. The rod big end mains, cases etc are designed for the pressure and load that the standard bore puts on them, bigger increases that so it WILL wear it out faster

Buy a bigger bike or ride this one to its full potential

TB

Bike has blown up twice but not from the big bore kit. One was from cam timing ( me having the inlet cam advanced to much and not checking valve to piston clearance at TPD) valve hitting piston with STD barel and STD piston. Second time was big end with Std barel and high comp piston fitted. So that was a full strip and rebuild. All new bearing and new oil pump and rebuilted crank (should have fitted a 4mm stroker crank at the time). The STD barel was damaged so i fitted a new Athena 440 hi comp kit and have never had a problem. Went for the Athena kit because of the bigger water jackets.
Bana

[GregMember]

Sorry Bana my facts weren’t exactly correct time age etc :blush: and it wasn’t a go at you personally it’s the only DR I know that has been extensively modified. It was reliable as the day was long before any work was done, as we rode everywhere together in those days it was always there purring away. The point I was and am making is normally the more you modify an engine for performance gains the more unreliable it becomes as we both know. That’s not mentioning time, effort, money etc that you have done trying cams, dyno testing, jetting, air intakes and now exhausts. Don’t get me wrong I like fiddling as much as the next mechanic and there is no price on a labour of love and a quick bike in the end.
Yes it’s been reliable since the last rebuild but as you would admit you have really ridden it much either like the old days, I would guess knowing you and your 2 job schedule and say it hasn’t done 3000kms?? To a stock DR400 3000kms isn’t a run to the local store. Much bigger and safer performance gains to be made with correctly setup suspension IMO was all I meant.

It was great catching up on the way back from Cobar when Nickj and I bumped into you and I would like to come for a ride with you and Bob when he is back. I will stay in touch

TB

[Darran wrightMember]

All good TB. You are right on the money when you start making them bigger and better there will be some pain. But as we all know you can never have enough power.
Bana

[Author]

Posts