IP2 engine trim

[gripper]

When I rebuilt my engine I left off the two covers that fit above the carb to engine pipes in an effort to improve the airflow past the engine and keep things . My temperature gauge generally stays around the 100 degree mark, occasionally slightly warmer. I recall prior to the rebuild the engine running much hotter. Unless the engine is properly warmed up it doesn't seem to perform well with what seems like a huge flat spot. (probably a slight misfire) It also doesn't drive smoothly until the temperature switch has knocked the digital ignition back to retarded. I'm tempted to refit the covers to bring the temperature up a little higher. Any thoughts on this matter?

[Richard Negus]

I too like the idea of leaving the covers off and gaining a bit of ventilation to the back of the engine - but I can't see it making much difference to the speed of engine warm-up. I do believe that an overhauled engine will be more efficient than a worn one, putting less heat into the castings and running cooler.Perhaps a temperature switch that closes at a lower temperature? They are a catalogue item with many temperature options; try RS or Farnell, or perhaps even Maplin.Those covers may be there as a safety item, keeping out debris that might conceivably jam the throttle levers in the open position. Sodde's Law would almost certainly apply.

[Interpol2471]

My IP2 engine also runs around the 100c mark, is your engine now Moly'd?I also find it runs a lot better when warm but found standard C8E or C9E plugs seem to work better when cold than the iridium plugs.WHAT IS YOUR PLUG COLOUR LIKE?

[johnbirchjar]

Hi Guys,my Classic runs at almost 150c,I've taken the carb;covers off to see if the old girl will run a bit cooler,hope so,if she do's I will make up some covers and drill them for ventilation,has anyone else tried this?regards,J.B.

[gripper]

Changed my Iridium plugs for standard C8E and there seems to be some improvement in initial running immediately after start. Not sure I would go to the bother of making up covers with holes. Now we've had a spot of warm weather the running temp is up to about 120

[rustynuts]

I would take any temperature reading from the gauge with a pinch of salt. By now you have at least 20 year's worth of wear and corrosion which will have altered the characteristic of the gauge and the thermocouple. They probably weren't even that accurate when new; you pay about £600 in today's money for a decent industrial quality analogue thermocouple gauge.About all it can tell you is whether your engine is running a bit hotter or a bit cooler than normal.

[johnbirchjar]

Hi guys,since taking the carb:covers off the Classic the old girl seems to run quite a bit cooler,(110/120,)but I have yet to do a long fast run,I will report anon,regards,J.B.

[johnbirchjar]

Reporting back as promised re: the last entry,blasting up to Gawthorpe Hall & back revealed that removing the covers from the rear of the engine made very little differance to the engine temp:still almost 150c(145?) at sustained high'ish speeds(80-90)but droped back to 120c at 70-75,is 150c to hot to sustain for long stretches of motorway?and is it worth a knackered engine for another 10/15 miles per hour?your thoughts guys?ride safe,J.B.

[Interpol2471]

John I think those temperatures are pretty normal it's over 200+ that trouble begins if I remember correctly. Maybe you could vent the lower fairing panels as I have, this made a great difference you can feel the heated air flow as you go along. I did the same to Frank's bike and I think even Richard was surprised at the result.

[johnbirchjar]

Hi 2471,My bike is a Classic, fitted with a3/4 fairing from a Triumph 900 Sprint Tripple,and the air flow is vertually the same as a "naked" Classic,thanks anyway,regards,J.B.

[Interpol2471]

Crumbs you should be running lovely and , today on the run down to the motorcycle ride in at Beaulieu even in the New Forest Traffic I only managed about 150C tops. Maybe I will have to remove my lowers to see what difference that makes to me?Mind you I dont trust the old VDO temperature gauge that much anyway