Been Around the Block
Wow! This is fantastic... Is the headlight/speedo a stock unit that came on these bikes?
The tach/speedo is by speedhut. I fit a screw in retainer ring into a universal headlight to hold it. The details are on page9-14cb360j said:Wow! This is fantastic... Is the headlight/speedo a stock unit that came on these bikes?
doc_rot said:Yes. We rode out on highway 20 day 1
squish at the edge was about .040" The ticking had a ring to it, like a rattle almost. it didn't sound like detonation. It also was only coming from one side.der_nanno said:The last bit is where I am coming from: Ticking sound and judging by how white the oil-deposits are, extreme combustion chamber temps, that could quite well be indicative of some sort of detonation. What's your squish clearance and do you have a built in squish area to keep things cooler? (By the looks of it, the chamber appears to be a hemisphere...)
teazer said:Some pin galling but no signs of detonation on pistons or the head.
Are you sure about that 220 psi number? That's really high - as in 15:1 type high. I would get a set of rings, clean up the carbon and find a way to get the compression down or arrange for a truck with 112 Octane gas to follow you around. I would also go richer on the midrange which is where the motor spends most of its time.
You might get away with retarding the timing but I'm not a big fan of that. What do the plugs look like? do they show signs of overheating on either center or side electrodes and what heat range are they?
doc_rot said:why would it only be in one cylinder though? and why would it get worse over time? i guess it couldnt hurt to add a knock sensor. Nanno - can you recommend a knock sensor to retro fit? any tips on doing so? thanks
der_nanno said:The reason why it's only on one cylinder can be quite a few, the most harmless being slight differences in piston height or ever so slightly twisted crank (not sure if the 750 is a pressed roller crank like on the 900s and 1000s/1100s).
With regards to a knock sensor, ages ago I built this, using (I think) a Nissan knock sensor, but pretty much any sensor will work, it might be tuned to slightly different frequencies, depending on which car you take it from.
Also judging by your last post's pictures: you have some engraining and perhaps even slight erosion on the exhaust valve, suggesting that combustion chamber is THROUGH THE ROOF. Your 0.040" squish clearance (roughly 1.016mm), is right on the limit of where a squishband becomes effective. So tightening that up to 0.90 or 0.85 mm (if it's a plane-bearing crank) will cool down the ignition notably. My TR1 lost about 20 to 25 degrees of oil-temperature due to improved squish (from 1.5 to 1.6mm down to 0.95 and 1.00), just from the more effective mix in the combustion chamber.