https://www.kiwibiker.co.nz/forums/blog.php/7424-The-V-Twin-Project Kiwi Biker - New Zealand motorcycle community en Sun, 03 May 2026 03:18:43 GMT vBulletin 20 https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/rss.jpg https://www.kiwibiker.co.nz/forums/blog.php/7424-The-V-Twin-Project https://www.kiwibiker.co.nz/forums/entry.php/221-The-V-Twin-Project Fri, 27 Jul 2007 11:01:19 GMT So we had a Block and a lot of bits. The first thing that we had to get our head around was what the previous guy had been thinking for how every thing would go together.

There were some things that were obvious problems needing solutions and a few things that I didn't agree with that he had done in design. That happens, no one is every completely right. The main problems were getting the crank balanced, figuring out the oil flows and figuring out how to do the cam chains. Some of these problems are only now being fully solved 3 months later.

The Crank

Because we wanted to use the standard crank to make life cheaper and more straight forward (cough, cough yeah right) the crank needed to be rebalanced to fifty percent ( 90 degree v-twin standard) of the non rotating mass to accommodate the extra weight on the crank. This meant a lot more mass to the counter balance because
1 the single had a light crank shaft to start
2 it used a balance shaft which we weren't
3 we were adding a lot more metal to the engine (longer pin, piston, conrod and gudgen pin) .

This all meant adding very dense Mallory metal (twice as dense steel) to the counter weights. We shopped around as decided on Lynn Rodgers because he is amazing, has helped the team before and is very knowledgeable. This was the start of a long process that I will go into in another post

The Cam Chains

The second major problem, for the engine, was the cam chains. For simplicity we kept the chains on the same side to start with (we didn't want to have to run the cam backwards). This meant that one of the cam chains ran right into the main bearing because of the offset for the con rods. Oh. Shit. Bugger. This started the process of finding out if smaller bearings would do the job, how would we do the chain guides, and how am I going to make a cam chain sprocket that
1 needs to go on between two things of larger diameter,
2 is smaller size than any standard
3 is a chain profile that no gear cutter in Auckland has ever seen. (Yamaha proprietary information damn it)

The Oiling

The final major problem, (if the ones above weren’t enough) was to figure the oiling. there was scavenge points in the block but in bad positions, there were no points organised where I could mount a belt or chain set up and I had no idea how much oil was required for the engine. This was a big learning curve for me and I have learned a lot from it about oiling for engines and bearings.

I later posts I will talk about each of these and what we have done about them. Currently we are getting close to starting the engine on the dyno. (Fingers crossed.) ]]> Tints https://www.kiwibiker.co.nz/forums/entry.php/221-The-V-Twin-Project https://www.kiwibiker.co.nz/forums/entry.php/207-The-V-Twin-Project Fri, 27 Jul 2007 09:08:55 GMT I picked up this project part way. i can't claim to have had all of the great ideas.

The idea of a custom V-Twin engine for the formula sae car had been around for a few years in the Auckland team and an old Yamaha Vision engine was dyno’ed and played with to try and get some rough data.

A team member was dead set on the idea of a V twin, was given a bit of cash and he started developing ideas for how a v twin could work. Over a year he came up with the idea that I am finishing of using two single cylinder dirt bike engines on a common crank.

He did the basic CAD work for the engine, started on the crankcase, and started getting the needed bits of engines. He basically got it to the point that this is how everything will sit, here is a list of things that I haven't sorted, have fun. ]]> KoroJ https://www.kiwibiker.co.nz/forums/entry.php/207-The-V-Twin-Project https://www.kiwibiker.co.nz/forums/entry.php/208-The-V-Twin-Project Thu, 12 Jul 2007 00:02:00 GMT Formula SAE was developed in the United States of America in 1981 by the Society of Automotive Engineers (SAE) to be used as an educational tool to develop university engineering students' knowledge and skills. In 2000 the first Formula SAE competition was held in Australia. Since then the Australian event has grown to be contested by over 25 universities from Australia, America, Japan and Europe. Formula SAE events are also run in the UK and Japan.

The year long competition comprises of students designing and constructing a small formula style racecar. These cars have specifications to limit physical dimensions and engine size to ensure that the competition is not just a race, but is run as an engineering competition where students' imagination, creativity, skills, and knowledge are all tested. The competition event held in December each year at the Victoria University Werribee campus, near Melbourne covers three days of scrutineering, static and dynamic events.

The static events; worth 325 out of the 1000 points, comprise a design report, a cost report, and a presentation to judges. The dynamic events are run as individual time trials, and make up the remainder of the marks. They consist of an acceleration test, skid pad test, autocross event, and a fuel economy and endurance race.

The premise of the competition is that a manufacturing firm has engaged students to design and produce a prototype racecar. The car must be able re-producible at a cost of less than US$25,000. ]]> Tints https://www.kiwibiker.co.nz/forums/entry.php/208-The-V-Twin-Project https://www.kiwibiker.co.nz/forums/entry.php/206-The-V-Twin-Project Wed, 11 Jul 2007 11:15:14 GMT Gidday My name is Craig and I’m a fourth year mechanical engineering student at the University of Auckland. Also while I have been at university I have been part of the University of Auckland Formula SAE team ( www.FSAE.co.nz ). As part of my degree I have to do a project about something... Gidday
My name is Craig and I’m a fourth year mechanical engineering student at the University of Auckland. Also while I have been at university I have been part of the University of Auckland Formula SAE team ( www.FSAE.co.nz ). As part of my degree I have to do a project about something engineering based. For this project I have decided to put two single cylinder dirt bike engines onto a common crank to make a V-twin.
There are two reasons why I’m doing this project;

1: I think that when the engine is finished it will be the future for the team and will be lighter, more reliable and a better over all package than the current engine.

2: I didn't want to do a boring project like measuring the efficiency of a clothes dryer which had been done for the last three years (no offence Fisher and Paykel)

So this is the story of the engine so far. Over the next couple of weeks I will bring the blog up to were we are now. All going well.

There are also some posts on the forums about it if you want to read them. ]]> Tints https://www.kiwibiker.co.nz/forums/entry.php/206-The-V-Twin-Project