Is this head ok?

**Mon Jun 01, 2009 1:07 pm » Post: #1 » Download Post**

Have just started the rebuild of my long term dead MC21.

Opionions on this head please - I'm assuming that's some detonation damage:

I'm reluctant to try wet n drying it as that'll reduce the compression...
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**Mon Jun 01, 2009 2:22 pm » Post: #2 » Download Post**

ive got some in a similer condition,i would agree its detonation damage.when my rs head was damaged like that i was steered away from doing anything with it by trevor smedly who tuned my engines.i had to just get another and tune it again Rolling Eyes

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**Mon Jun 01, 2009 4:46 pm » Post: #3 » Download Post**

that ones really bad! the front heads always seem to suffer loads more det damage than the rear,

**Mon Jun 01, 2009 5:01 pm » Post: #4 » Download Post**

Hmmm. Thought as much.

I have a spare rear head, so it's a good time for the conversion. I need the HRC hose to go with the head. Any suggestions for sources?

I've just ordered a bunch of stuff from Lings (nuts, bolts, washers, thermostat etc). Very impressed with their site - you can search the part number by copying and pasting from this site's parts manual. Sadly they don't list the HRC hose...
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

**Mon Jun 01, 2009 5:04 pm » Post: #5 » Download Post**

SP front head? Got one here if you want it Dave, the price will be a pint or maybe two Wink

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**Mon Jun 01, 2009 5:14 pm » Post: #6 » Download Post**

Thanks Fontyyy, but I have a head - it's the hose I need to do the conversion.
_________________
MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

**Mon Jun 01, 2009 6:28 pm » Post: #7 » Download Post**

pretty sure there listed on the tyga site

**Mon Jun 01, 2009 7:34 pm » Post: #8 » Download Post**

That head can still be brought back to life , all you need is to have it recut .
What squish were you using , squish and compression are linked .

Tyga sell those special hoses .

Cheers
Neal

**Mon Jun 01, 2009 7:47 pm » Post: #9 » Download Post**

Standard SP - never touched the stock stuff. Since the 'normal' front head isn't as efficient as the rear, and I also have a rear ready to go on the front, it makes sense to do the swap - and I guess a hose will be cheaper than ahaving the head machined.

Thanks anyway. Cool

_________________
MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

**Mon Jun 01, 2009 8:49 pm » Post: #10 » Download Post**

Dave Ett had a head that had seemed some det.

Was going to spin that into a limerick but I can see a FAIL! happening.

Even a real cheap ba$tard as myself would probably not run that head. If you do go for the conversion, you don't need the HRC hose. Just get radiator hosing and loop it from the head to the thermomstat. I think I used a ~24" piece on my MC28 for about 5 years without issue.