How many hours on the dyno?

I am converting a 2 stroke carb bike to EFI. I do not own a dyno and will have to take it to a shop for tuning. It will cost $130 per hour.

Of course I will get the bike idling and running in my shop, using conservative maps. But then I will want to take it to the dyno for final tuning.

This will be my first tuning, but I am *very* familiar with EFI engines, embeded electronics, computers, software and mechanics. So I have skills.

Given the above, do you have any suggestions on how many hours I should expect for my tuning session? How many hours did your first session take?

thanks!

Hi Don, you've kind of jumped in the deep end a b it here with a 2 stroke engine! It's important to mention that at this stage I haven't had any personal experience with 2 stroke tuning but it does differ a little from 4 stroke engines, particularly with regard to AFR targets. My research has suggested that you will need to tune a little richer than what you'd consider for a typical 4 stroke engine and I'd suggest you start by reading Graham Bell's '2 Stroke Performance Tuning'. It's also common on a 2 stroke engine to rely heavily on EGT to aid with selecting a suitable AFR.

In terms of dyno time I'd suggest for your very first tuning session you should be able to get the basics dialled in within 2-3 hours but if you want to thoroughly fine tune everything then this could be in the range of 4-5 hours. It would help speed up the process if you can make sure the engine runs and revs cleanly before heading to the dyno. I'd also cover off the basics such as checking your base ignition timing.

Hi Andre - thanks for the reply. Thanks for the tips on the book. I do have them and they are helpful. I keep re-reading them!

Once I found that your intro course has road based tuning I signed up. I will still tune for dyno, but will get as much done on the road before hitting the dyno.

thanks!