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| 1978 CR250 - Need Top End Advise https://vintagedirtbikeforums.alp-sys.com/viewtopic.php?f=21&t=4344 |
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| Author: | sting66cp [ Tue Aug 12, 2014 10:36 am ] |
| Post subject: | 1978 CR250 - Need Top End Advise |
The chrome plating on my 78 cr250 cylinder is starting to come off. This cylinder has a bridged exhaust port, I thought someone in the past told me that the 79's had a bridged exhaust port and the 78's didn't, is this accurate? Here are the engine numbers: CR250ORE 1005432 Are there any differences between a 78 and 79 cylinder? What are my options for repairing this, and what is you experience with it. Thanks for any advise on this. |
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| Author: | tnr [ Wed Aug 13, 2014 1:06 am ] |
| Post subject: | Re: 1978 CR250 - Need Top End Advise |
Another option would be to have a new liner pressed in. Then you would have over bores available. |
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| Author: | mxcentral [ Wed Aug 13, 2014 4:59 pm ] |
| Post subject: | Re: 1978 CR250 - Need Top End Advise |
79 cylinder has a bridge in the intake port for longer piston life . Send it out and get it plated . Don't go the sleeve route as the sleeve is a huge heat sink . We do a nice 2mm overbore with porting to match if you need a little extra grunt . |
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| Author: | b-joe [ Thu Aug 14, 2014 9:34 am ] |
| Post subject: | Re: 1978 CR250 - Need Top End Advise |
my cylinders are nicasil replated, much better than chrome plating or iron liners. |
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