2015 Beta 350 RR EFI Long Term Update #1

2015 Beta 350RR EFI Long-Term Test Update

Getting to know the Beta

So we’ve logged 40-hours on our 350RR and wanted to give readers an update on what we’ve done to the bike and how it’s holding up.

Time: 40 hours

Miles: 949

Maintenance:

4-Oil changes (both engine and transmission)

2-oil filter changes

Air filter cleaned as needed

Serviced suspension fluids (shock and fork)

Checked and adjusted valves

Removed horn

Changed out grips to ODI Emig Clamp-on grips.

Notes:

The shock faded under heavy use during our testing so we decided the first step was a service to see if there was anything amiss. The oil was burnt a little, but not bad at 15-hours and we suspected there was a little air in the shock as well. Additionally the nitrogen pressure was at 130 PSI where we’ve been told 150 PSI is ideal on the Sachs shock. We used Joe Gibbs Racing shock fluid on the rebuild and can report a definite improvement on the performance of the shock and it has much more resistance to fading, though we can still get it to soften up with consistent whoop pounding where we believe the oil is getting past the piston band on the shock’s piston. We will look into some valving updates and possibly different springs to take some of the workload off the piston and valving.

The fork oil definitely needed a service too. We raised the oil level to add bottoming resistance and put it back together. They also worked a little bit better.

As the engine gets more time on it, it is revving more freely, especially in the mid-range where the Beta was already impressive.  It still runs strong and sounds mechanically tight.

On our last ride the bike was noticeably harder to start (with the electric starter even) and stalled a little bit which was not normal. So we checked the valve clearance and the left intake valve had almost no clearance. The left exhaust was just under its tight side setting so we shimmed them into proper clearance using Hot Cams 10mm OD valve shims. Working on the valves of the Beta is a little more complicated than some other bikes, at least in getting the cover off. It requires removing the upper engine mount and getting the wires out of the way, then finding the right move to slide the cover out. Feeler gauges with a long narrow reach help out a lot. Setting the shims under the rocker arms isn’t that tough but a small magnet on an arm helps. We zip-tied the cam chain onto the cam sprockets to keep the timing set and were easily able to lift the cams out of the way. Some of the cam journal bolts, which are crowned, are hard to get at and a good 10mm wrench will help. The torque is critical as the tolerances can change easily based on how tight you torque the cam journal bolts and getting a torque wrench on a couple of them is impossible. Be careful with the valve cover gaskets, especially the center spark plug one. Adding a little silicone is a good idea to prevent oil from seeping.

Hopefully soon we’ll get the chance to also play with the FI mapping and ignition timing as well as the stepper motor on the FI body to see if we can tune it a little better for very low RPM and technical situations where our bike has a slight stumble.

For the rest of the bike nuts and bolts have been staying tight and even the spokes have only needed one tightening. The chain and sprockets look fine but we’ve been in very little mud, really.