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Discussion Starter #1
Hi all,

I've not long bought a Honda SP1 after owning a Suzuki TL1000R for 9 years, but am a little disappointed with the performance. It's doesn't seem a patch on the TLR at all, either pick up wise or top end speed. I assume there must be something wrong, with all the positive wriite ups online. Does anyone know what to look out for? Basically I'm going to check the general things like plugs and timing but is are there any common problems which would cause the lack of performance?

Cheers
Dave
 

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What sort of performance differences are you seeing?

The RC51 and TLR were similar in performance engine-wise.
The main advantage of the RC51 was the better overall chassis design.
 

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Discussion Starter #3
Hello,

I have done a plug check and compression check. The rear pot is 175psi and the front has 130psi so there's quite a bit of difference between the two but the bike appears to run spot on. The timing's also spot on.

Basically the bike doesn't seem to be as powerful as my TLR all the way through the rev range and seems to really eat fuel.

Does anyone know what the compression should be on each cylinder? I assume the compression being down on the front cylinder will have an impact.

Cheers
Dave
 

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Fresh, the engine should have 176 PSI.
The rear is not too bad at -1 PSI from spec, but that front has some issues.
That's over 45 PSI down from the front.

Does it smoke from your exhaust?
If not, how's your valve clearances on the front?
If the valve clearance is way too tight, it may not be seating the valves properly.
 

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Discussion Starter #7
Thanks to all who have replied. I will be checking the clearances this evening so fingers crossed it will be a shim issue where I don't need to strip the top end totally.

Cheers
Dave
 

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Discussion Starter #8
I forgot to say, there's no smoke at all. It's doesn't use any oil but the bike is a bit thirsty.

If it turns out to be the rings I will think about upgrading to high compression pistons at the same time. Do I need to upgrade the injectors at the same time?

Cheers
Dave
 

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Discussion Starter #10
Hi Steve,

I've stripped off the top end and found the front pot has a score all the way down. Time for the engine out me thinks.



I assume it's a full engine strip to get the pistons out.

Cheers
Dave
 

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You have some photos of the cylinder scoring from a different angle?
From this perspective the scoring does look too awfully bad.
But from a different angle it might show much worse.
The cylinder can be over bored twice from STD, .25mm and .50mm, with matching oversize piston and rings to match.
Anything beyond .50mm will require boring and replating with nikasil.
Millenium Technologies is the company that has done many RC51 engines.
 

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Discussion Starter #13
Morning all,

I'll post some pics up tonight of the stripped motor. I'm really impressed how well designed the engine is.

Cheers
Dave
 

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Discussion Starter #14
Hi all,

Right I'm just in the process of getting my parts list together

Crank Bearings - MCF-F-780 OXOI (taken off the bearing) the colour of the bearing is not apparent
Conrod Bearings - MCF070F (taken off the bearing) the colour of the bearing is not apparent
Oversize 0.5 Rings - 13031-MCF-305 x 2
Front Head Gasket - 12251-MCF-003
Rear Head Gasket - 12252-MCF-003
Grey Engine Bolts - ???
Generator Gasket - 11636-MCF-000
Clutch gasket - 11356-MCF-000
Front Engine Bolt - 90102-MCF-000
Front Adjuster - 90152-MCF-000
Front 0.5 Piston - 13103-MCF-305
Rear 0.5 Piston - 13107-MCF-305

Can anyone help with the red part numbers?

Cheers
Dave
 

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Hi all,

Right I'm just in the process of getting my parts list together

Crank Bearings - MCF-F-780 OXOI (taken off the bearing) the colour of the bearing is not apparent
Conrod Bearings - MCF070F (taken off the bearing) the colour of the bearing is not apparent
Oversize 0.5 Rings - 13031-MCF-305 x 2
Front Head Gasket - 12251-MCF-003
Rear Head Gasket - 12252-MCF-003
Grey Engine Bolts - ???
Generator Gasket - 11636-MCF-000
Clutch gasket - 11356-MCF-000
Front Engine Bolt - 90102-MCF-000
Front Adjuster - 90152-MCF-000
Front 0.5 Piston - 13103-MCF-305
Rear 0.5 Piston - 13107-MCF-305

Can anyone help with the red part numbers?

Cheers
Dave
The gray special bolts are pn 90009-MCF-000 (qty 4).
Reference Item 9 in the link below.
http://www.mrcycles.com/fiche_section_detail.asp?section=156013&category=MOTORCYCLES&make=HONDA&year=2002&fveh=3621

To determine both crankshaft main bearings and connecting rod bearings, here's a cross-reference (be sure and consult the dealer's parts list)


Then cross-reference the bearing (crank or rod) Bearing "letter" to part number.

For instance, for a 2002 RC51, the crankshaft and crankcase cross-reference of C3 equates to bearing color code Blue.
Then color code Blue = Bearing A.
Crankshaft Bearing A = pn 13313-MCF-003 (referring to Item 11 in the link below)
http://www.mrcycles.com/fiche_section_detail.asp?section=156014&category=MOTORCYCLES&make=HONDA&year=2002&fveh=3621

The rod bearings are determined in the same manner.
 

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Hi all,

Right I'm just in the process of getting my parts list together

Crank Bearings - MCF-F-780 OXOI (taken off the bearing) the colour of the bearing is not apparent
Conrod Bearings - MCF070F (taken off the bearing) the colour of the bearing is not apparent
Oversize 0.5 Rings - 13031-MCF-305 x 2
Front Head Gasket - 12251-MCF-003
Rear Head Gasket - 12252-MCF-003
Grey Engine Bolts - ???
Generator Gasket - 11636-MCF-000
Clutch gasket - 11356-MCF-000
Front Engine Bolt - 90102-MCF-000
Front Adjuster - 90152-MCF-000
Front 0.5 Piston - 13103-MCF-305
Rear 0.5 Piston - 13107-MCF-305

Can anyone help with the red part numbers?

Cheers
Dave
The gray special bolts are pn 90009-MCF-000 (qty 4).
Refer to Item 9 at the link below
http://www.mrcycles.com/fiche_section_detail.asp?section=156013&category=MOTORCYCLES&make=HONDA&year=2002&fveh=3621

To determine both crankshaft main bearings and connecting rod bearings, here's a cross-reference (be sure and consult the dealer's parts list)


Then cross-reference the bearing (crank or rod) Bearing "letter" to part number.

For instance, for a 2002 RC51, the crankshaft and crankcase cross-reference of C3 equates to bearing color code Blue.
Then color code Blue = Bearing A.
Crankshaft Bearing A = pn 13313-MCF-003 (referring to Item 11 in the link below)
http://www.mrcycles.com/fiche_section_detail.asp?section=156014&category=MOTORCYCLES&make=HONDA&year=2002&fveh=3621
 

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These bikes are so reliable I'm surprised they didn't give you a strange look when ordering piston, rings, and bearings.
 
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